PL/SQL Interview Questions

SQL / PL SQL Questions
How do you convert a date to a string?What is an aggregate function?What is the dual table?What are cursors? Distinguish between implicit and explict cursors?Explain how cursors are used by Oracle?What is PL/SQL? Describe the block structure of PL/SQL?What is a nested subquery?What are the various types of queries ?Which of the following is not a schema object : Index, table, public synonym, trigger and package ?What is dynamic sql in oracle?What is the difference between a package, procedure and functionWhat is the difference between delete, drop and truncating a tableHow many triggers are supported in OracleAre you aware of FLASHBACK concept ? What is it?Describe oracle’s logical and physical structure?What is data dictionaryWhat is the use of control filesHow would store XML data in table ? What data type would be used for the columns?Difference between post and commit?Difference between commit and rollback?What are savepoints?Difference between a View and SynonymHow would you fetch system date from oracleWhat is the difference between primary key, unique key, foreign key?What is the difference between NO DATA FOUND and %NOTFOUNDWhat is cursor for loopWhat are cursor attributesWhat will you use in Query : IN or EXISTS? WhyExplain the difference between a data block, an extent and a segment.What's the difference between logical and physical I/O?What is an anonymous block?What is a PL/SQL collection?How can you tell if an UPDATE updated no rowsHow can you tell if a SELECT returned no rowsDB concepts:Physical Database Structure1. Datafiles2. Redo log files3. Control files.Logical Structures1. TableSpaces2. DB Schema Objects.Segments,Extents and Data BlocksOracle background processes1. PMON2.SMON3.DBWR4.LGWR5.ARCH6.RECOA synonym is an alias for a table, view, sequence, create public synonyms that make the base schema object available for general, system-wide use by any database user.Indexes are created to increase the performance of data retrieval

PL/SQL interview qiuestions
Which of the following statements is true about implicit cursors?
Implicit cursors are used for SQL statements that are not named.
Developers should use implicit cursors with great care.
Implicit cursors are used in cursor for loops to handle data processing.
Implicit cursors are no longer a feature in Oracle.
Which of the following is not a feature of a cursor FOR loop?
Record type declaration.
Opening and parsing of SQL statements.
Fetches records from cursor.
Requires exit condition to be defined.
A developer would like to use referential datatype declaration on a variable. The variable name is EMPLOYEE_LASTNAME, and the corresponding table and column is EMPLOYEE, and LNAME, respectively. How would the developer define this variable using referential datatypes?
Use employee.lname%type.
Use employee.lname%rowtype.
Look up datatype for EMPLOYEE column on LASTNAME table and use that.
Declare it to be type LONG.
Which three of the following are implicit cursor attributes?
%found
%too_many_rows
%notfound
%rowcount
%rowtype
If left out, which of the following would cause an infinite loop to occur in a simple loop?
LOOP
END LOOP
IF-THEN
EXIT
Which line in the following statement will produce an error?
cursor action_cursor is
select name, rate, action
into action_record
from action_table;
There are no errors in this statement.
The command used to open a CURSOR FOR loop is
open
fetch
parse
None, cursor for loops handle cursor opening implicitly.
What happens when rows are found using a FETCH statement
It causes the cursor to close
It causes the cursor to open
It loads the current row values into variables
It creates the variables to hold the current row values
Read the following code:10. CREATE OR REPLACE PROCEDURE find_cpt11. (v_movie_id {Argument Mode} NUMBER, v_cost_per_ticket {argument mode} NUMBER)12. IS13. BEGIN14. IF v_cost_per_ticket > 8.5 THEN15. SELECT cost_per_ticket16. INTO v_cost_per_ticket17. FROM gross_receipt18. WHERE movie_id = v_movie_id;19. END IF;20. END;
Which mode should be used for V_COST_PER_TICKET?
IN
OUT
RETURN
IN OUT
Read the following code:22. CREATE OR REPLACE TRIGGER update_show_gross23. {trigger information}24. BEGIN25. {additional code}26. END;
The trigger code should only execute when the column, COST_PER_TICKET, is greater than $3. Which trigger information will you add?
WHEN (new.cost_per_ticket > 3.75)
WHEN (:new.cost_per_ticket > 3.75
WHERE (new.cost_per_ticket > 3.75)
WHERE (:new.cost_per_ticket > 3.75)
What is the maximum number of handlers processed before the PL/SQL block is exited when an exception occurs?
Only one
All that apply
All referenced
None
For which trigger timing can you reference the NEW and OLD qualifiers?
Statement and Row
Statement only
Row only
Oracle Forms trigger
Read the following code:30. CREATE OR REPLACE FUNCTION get_budget(v_studio_id IN NUMBER)31. RETURN number IS32. 33. v_yearly_budget NUMBER;34. 35. BEGIN36. SELECT yearly_budget37. INTO v_yearly_budget38. FROM studio39. WHERE id = v_studio_id;40. 41. RETURN v_yearly_budget;42. END;
Which set of statements will successfully invoke this function within SQL*Plus?
VARIABLE g_yearly_budget NUMBEREXECUTE g_yearly_budget := GET_BUDGET(11);
VARIABLE g_yearly_budget NUMBEREXECUTE :g_yearly_budget := GET_BUDGET(11);
VARIABLE :g_yearly_budget NUMBEREXECUTE :g_yearly_budget := GET_BUDGET(11);
VARIABLE g_yearly_budget NUMBER:g_yearly_budget := GET_BUDGET(11); 43. CREATE OR REPLACE PROCEDURE update_theater44. (v_name IN VARCHAR v_theater_id IN NUMBER) IS45. BEGIN46. UPDATE theater47. SET name = v_name48. WHERE id = v_theater_id;49. END update_theater;
50. When invoking this procedure, you encounter the error:ORA-000: Unique constraint(SCOTT.THEATER_NAME_UK) violated.
How should you modify the function to handle this error?
An user defined exception must be declared and associated with the error code and handled in the EXCEPTION section.
Handle the error in EXCEPTION section by referencing the error code directly.
Handle the error in the EXCEPTION section by referencing the UNIQUE_ERROR predefined exception.
Check for success by checking the value of SQL%FOUND immediately after the UPDATE statement.
Read the following code:52. CREATE OR REPLACE PROCEDURE calculate_budget IS53. v_budget studio.yearly_budget%TYPE;54. BEGIN55. v_budget := get_budget(11);56. IF v_budget < 3000057. THEN58. set_budget(11,30000000);59. END IF;60. END;
You are about to add an argument to CALCULATE_BUDGET. What effect will this have?
The GET_BUDGET function will be marked invalid and must be recompiled before the next execution.
The SET_BUDGET function will be marked invalid and must be recompiled before the next execution.
Only the CALCULATE_BUDGET procedure needs to be recompiled.
All three procedures are marked invalid and must be recompiled.
Which procedure can be used to create a customized error message?
RAISE_ERROR
SQLERRM
RAISE_APPLICATION_ERROR
RAISE_SERVER_ERROR
The CHECK_THEATER trigger of the THEATER table has been disabled. Which command can you issue to enable this trigger?
ALTER TRIGGER check_theater ENABLE;
ENABLE TRIGGER check_theater;
ALTER TABLE check_theater ENABLE check_theater;
ENABLE check_theater;
Examine this database trigger64. CREATE OR REPLACE TRIGGER prevent_gross_modification65. {additional trigger information}66. BEGIN67. IF TO_CHAR(sysdate, DY) = MON68. THEN69. RAISE_APPLICATION_ERROR(-20000,Gross receipts cannot be deleted on Monday);70. END IF;71. END;
This trigger must fire before each DELETE of the GROSS_RECEIPT table. It should fire only once for the entire DELETE statement. What additional information must you add?
BEFORE DELETE ON gross_receipt
AFTER DELETE ON gross_receipt
BEFORE (gross_receipt DELETE)
FOR EACH ROW DELETED FROM gross_receipt
Examine this function:73. CREATE OR REPLACE FUNCTION set_budget74. (v_studio_id IN NUMBER, v_new_budget IN NUMBER) IS75. BEGIN76. UPDATE studio77. SET yearly_budget = v_new_budget78. WHERE id = v_studio_id;79. 80. IF SQL%FOUND THEN81. RETURN TRUEl;82. ELSE83. RETURN FALSE;84. END IF;85. 86. COMMIT;87. END;
Which code must be added to successfully compile this function?
Add RETURN right before the IS keyword.
Add RETURN number right before the IS keyword.
Add RETURN boolean right after the IS keyword.
Add RETURN boolean right before the IS keyword.
Under which circumstance must you recompile the package body after recompiling the package specification?
Altering the argument list of one of the package constructs
Any change made to one of the package constructs
Any SQL statement change made to one of the package constructs
Removing a local variable from the DECLARE section of one of the package constructs
Procedure and Functions are explicitly executed. This is different from a database trigger. When is a database trigger executed?
When the transaction is committed
During the data manipulation statement
When an Oracle supplied package references the trigger
During a data manipulation statement and when the transaction is committed
Which Oracle supplied package can you use to output values and messages from database triggers, stored procedures and functions within SQL*Plus?
DBMS_DISPLAY
DBMS_OUTPUT
DBMS_LIST
DBMS_DESCRIBE
What occurs if a procedure or function terminates with failure without being handled?
Any DML statements issued by the construct are still pending and can be committed or rolled back.
Any DML statements issued by the construct are committed
Unless a GOTO statement is used to continue processing within the BEGIN section, the construct terminates.
The construct rolls back any DML statements issued and returns the unhandled exception to the calling environment.
Examine this code93. BEGIN94. theater_pck.v_total_seats_sold_overall := theater_pck.get_total_for_year;95. END;
For this code to be successful, what must be true?
Both the V_TOTAL_SEATS_SOLD_OVERALL variable and the GET_TOTAL_FOR_YEAR function must exist only in the body of the THEATER_PCK package.
Only the GET_TOTAL_FOR_YEAR variable must exist in the specification of the THEATER_PCK package.
Only the V_TOTAL_SEATS_SOLD_OVERALL variable must exist in the specification of the THEATER_PCK package.
Both the V_TOTAL_SEATS_SOLD_OVERALL variable and the GET_TOTAL_FOR_YEAR function must exist in the specification of the THEATER_PCK package.
A stored function must return a value based on conditions that are determined at runtime. Therefore, the SELECT statement cannot be hard-coded and must be created dynamically when the function is executed. Which Oracle supplied package will enable this feature?
DBMS_DDL
DBMS_DML
DBMS_SYN
DBMS_SQL

Networking Interview Questions

Network engineer interview questions
OSPF
· Describe OSPF in your own words.
· OSPF areas, the purpose of having each of them
· Types of OSPF LSA, the purpose of each LSA type
· What exact LSA type you can see in different areas
· How OSPF establishes neighboor relation, what the stages are
· If OSPF router is stucked in each stage what the problem is and how to troubleshoot it
· OSPF hierarchy in the single or multi areas. Cool OSPF behavior in broadcast and nonbroadcast
· Draw the diagram of typical OSPF network and explain generally how it works, DR, BDR, election, ASBR, ABR, route redistribution and summarization
STP
· How it works and the purpose
· Diff types (SSTP, MSTP, RSTP) Cisco - PVST/PVST+
· root election
· Diff. port stages and timing for convergence
· Draw the typical diagram and explain how diff types of STP work
· What ports are blocking or forwarding
· How it works if there are topology changes
ACLs
· What are they
· Diff types
· Write an example if you want to allow and to deny…
· Well-known port numbers (DNS - 53 and etc…)
QOS
· What is that
· What is the diff b/w L2 and L3 QoS
· How it works
Network:
· Draw the typical network diagram you have to deal with
· explain how it works
· What part of it you are responsible
· firewall, what is that, how it works, how it is diff from ACLs
· What problems with the network you had had and how you solved it.
· What are the ways to troubleshoot the network, techniques, commands
· network security, ways to achieve it
Switching:
· VLANs
· STP
· How a L2 switch works with broadcast, unicast, multicast, known/unknown traffic
· VRRP, GLBP
· port monitoring and mirroring
· L3 switch, how it works
· PIM sparse and dense modes
^Back to Top
Windows admin interview questions
1. Describe how the DHCP lease is obtained. It’s a four-step process consisting of (a) IP request, (b) IP offer, © IP selection and (d) acknowledgement.
2. I can’t seem to access the Internet, don’t have any access to the corporate network and on ipconfig my address is 169.254.*.*. What happened? The 169.254.*.* netmask is assigned to Windows machines running 98/2000/XP if the DHCP server is not available. The name for the technology is APIPA (Automatic Private Internet Protocol Addressing).
3. We’ve installed a new Windows-based DHCP server, however, the users do not seem to be getting DHCP leases off of it. The server must be authorized first with the Active Directory.
4. How can you force the client to give up the dhcp lease if you have access to the client PC? ipconfig /release
5. What authentication options do Windows 2000 Servers have for remote clients? PAP, SPAP, CHAP, MS-CHAP and EAP.
6. What are the networking protocol options for the Windows clients if for some reason you do not want to use TCP/IP? NWLink (Novell), NetBEUI, AppleTalk (Apple).
7. What is data link layer in the OSI reference model responsible for? Data link layer is located above the physical layer, but below the network layer. Taking raw data bits and packaging them into frames. The network layer will be responsible for addressing the frames, while the physical layer is reponsible for retrieving and sending raw data bits.
8. What is binding order? The order by which the network protocols are used for client-server communications. The most frequently used protocols should be at the top.
9. How do cryptography-based keys ensure the validity of data transferred across the network? Each IP packet is assigned a checksum, so if the checksums do not match on both receiving and transmitting ends, the data was modified or corrupted.
10. Should we deploy IPSEC-based security or certificate-based security? They are really two different technologies. IPSec secures the TCP/IP communication and protects the integrity of the packets. Certificate-based security ensures the validity of authenticated clients and servers.
11. What is LMHOSTS file? It’s a file stored on a host machine that is used to resolve NetBIOS to specific IP addresses.
12. What’s the difference between forward lookup and reverse lookup in DNS? Forward lookup is name-to-address, the reverse lookup is address-to-name.
13. How can you recover a file encrypted using EFS? Use the domain recovery agent.
^Back to Top
Read more at TechInterviews.com
Network engineer/architect interview questions
1. Explain how traceroute, ping, and tcpdump work and what they are used for?
2. Describe a case where you have used these tools to troubleshoot.
3. What is the last major networking problem you troubleshot and solved on your own in the last year?
4. What LAN analyzer tools are you familiar with and describe how you use them to troubleshoot and on what media and network types.
5. Explain the contents of a routing table (default route, next hop, etc.)
6. What routing protocols have you configured?
7. Describe the commands to set up a route.
8. What routing problems have you troubleshot?
9. How do you display a routing table on a Cisco? On a host?
10. How do you use a routing table and for what?
11. What is a route flap?
12. What is a metric?
13. When do you use BGP, IGRP, OSPF, Static Routes?
14. What do you see as current networking security issues (e.g. NFS mounting, spoofing, one time passwords, etc.)?
15. Describe a routing filter and what it does.
16. Describe an access list and what it does.
17. What is a network management system?
18. Describe how SNMP works.
19. Describe the working environment you are currently in, e.g. frequent interruptions, frequent priority shifting, team or individual.
20. What do you use to write documentation? Editor? Mail reader?
21. What platform (s) do you currently work on at your desk?
22. How do you manage multiple concurrent high level projects?
23. Describe a recent short term stressful situation and how you managed it.
24. How do you manage a long term demanding stressful work environment?
25. Have you worked in an assignment based environment, e.g. work request/trouble ticket system, and if so, describe that environment.
26. Describe what network statistics or measurement tools you are familiar with and how you have used them.
27. Describe what a VPN is and how it works.
28. Describe how VoIP works.
29. Describe methods of QoS.
30. How does ToS bit work?
^Back to Top
CCNA/Cisco admin interview questions
1. You need to retrieve a file from the file server for your word processing application, which layer of the OSI model is responsible for this function?
1. Presentation layer
2. Application layer
3. Session layer
4. Transport layer
5. Datalink layer
2. You are working in a word processing program, which is run from the file server. Your data comes back to you in an unintelligible manner. Which layer of the OSI model would you investigate?
1. Application layer
2. Presentation layer
3. Session layer
4. Network layer
5. Datalink layer
3. The IEEE subdivided the datalink layer to provide for environments that need connectionless or connection-oriented services. What are the two layers called?
1. Physical
2. MAC
3. LLC
4. Session
5. IP
4. You are working with graphic translations. Which layer of the OSI model is responsible for code formatting and conversion and graphic standards.
1. Network layer
2. Session layer
3. Transport layer
4. Presentation layer
5. Which is the best definition of encapsulation?
1. Each layer of the OSI model uses encryption to put the PDU from the upper layer into its data field. It adds header and trailer information that is available to its counterpart on the system that will receive it.
2. Data always needs to be tunneled to its destination so encapsulation must be used.
3. Each layer of the OSI model uses compression to put the PDU from the upper layer into its data field. It adds header and trailer information that is available to its counterpart on the system that will receive it.
4. Each layer of the OSI model uses encapsulation to put the PDU from the upper layer into its data field. It adds header and trailer information that is available to its counterpart on the system that will receive it.
6. Routers can be configured using several sources. Select which of the following sources can be used.
1. Console Port
2. Virtual Terminals
3. TFTP Server
4. Floppy disk
5. Removable media
7. Which memory component on a Cisco router contains the dynamic system configuration?
1. ROM
2. NVRAM
3. Flash
4. RAM/DRAM
8. Which combination of keys will allow you to view the previous commands that you typed at the router?
1. ESC-P
2. Ctrl-P
3. Shift-P
4. Alt-P
9. Which commands will display the active configuration parameters?
1. show running-config
2. write term
3. show version
4. display term
10. You are configuring a router, which prompt tells you that you are in the privileged EXEC mode?
1. @
2. >
3. !
4. :
5. #
11. What does the command “IP name-server 255.255.255.255″ accomplish?
1. It disables domain name lookup.
2. It sets the domain name lookup to be a local broadcast.
3. This is an illegal command.
4. The command is now defunct and has been replaced by “IP server-name ip any”
12. The following selections show the command prompt and the configuration of the IP network mask. Which two are correct?
1. Router(config-if)#netmask-format { bitcount decimal hexadecimal }
2. Router#term IP netmask-format { bitcount decimal hexadecimal }
3. Router(config-if)#IP netmask-format { bitcount decimal hexadecimal }
4. Router#ip netmask-format { bitcount decimal hexadecimal }
13. Which layer is responsible for flow control with sliding windows and reliability with sequence numbers and acknowledgments?
1. Transport
2. Application
3. Internet
4. Network Interface
14. Which processes does TCP, but not UDP, use?
1. Windowing
2. Acknowledgements
3. Source Port
4. Destination Port
15. Select which protocols use distance vector routing?
1. OSPF
2. RIP
3. IGRP
4. PPP
^Back to Top
Read more at TechInterviews.com
Networking and Unix interview questions
What is UTP?
UTP — Unshielded twisted pair 10BASE-T is the preferred Ethernet medium of the 90s. It is based on a star topology and provides a number of advantages over coaxial media:
It uses inexpensive, readily available copper phone wire. UTP wire is much easier to install and debug than coax. UTP uses RG-45 connectors, which are cheap and reliable.
What is a router? What is a gateway?
Routers are machines that direct a packet through the maze of networks that stand between its source and destination. Normally a router is used for internal networks while a gateway acts a door for the packet to reach the ‘outside’ of the internal network
What is Semaphore? What is deadlock?
Semaphore is a synchronization tool to solve critical-section problem, can be used to control access to the critical section for a process or thread. The main disadvantage (same of mutual-exclusion) is require busy waiting. It will create problems in a multiprogramming system, where a single CPU is shared among many processes.
Busy waiting wastes CPU cycles.
Deadlock is a situation when two or more processes are waiting indefinitely for an event that can be caused by only one of the waiting processes. The implementation of a semaphore with a waiting queue may result in this situation.
What is Virtual Memory?
Virtual memory is a technique that allows the execution of processes that may not be completely in memory. A separation of user logical memory from physical memory allows an extremely large virtual memory to be provided for programmers when only a smaller physical memory is available. It is commonly implemented by demand paging. A demand paging system is similar to a paging system with swapping. Processes reside on secondary memory (which is usually a disk). When we want to execute a process, we swap it into memory.
Explain the layered aspect of a UNIX system. What are the layers? What does it mean to say they are layers?
A UNIX system has essentially three main layers:
. The hardware
. The operating system kernel
. The user-level programs
The kernel hides the system’s hardware underneath an abstract, high-level programming interface. It is responsible for implementing many of the facilities that users and user-level programs take for granted.
The kernel assembles all of the following UNIX concepts from lower-level hardware features:
. Processes (time-sharing, protected address space)
. Signals and semaphores
. Virtual Memory (swapping, paging, and mapping)
. The filesystem (files, directories, namespace)
. Pipes and network connections (inter-process communication)
What are the required components of Windows Server 2003 for installing Exchange 2003? - ASP.NET, SMTP, NNTP, W3SVC
What must be done to an AD forest before Exchange can be deployed? - Setup /forestprep
What Exchange process is responsible for communication with AD? - DSACCESS
What 3 types of domain controller does Exchange access? - Normal Domain Controller, Global Catalog, Configuration Domain Controller
What connector type would you use to connect to the Internet, and what are the two methods of sending mail over that connector? - SMTP Connector: Forward to smart host or use DNS to route to each address
How would you optimise Exchange 2003 memory usage on a Windows Server 2003 server with more than 1Gb of memory? - Add /3Gb switch to boot.ini
What would a rise in remote queue length generally indicate? - This means mail is not being sent to other servers. This can be explained by outages or performance issues with the network or remote servers.
What would a rise in the Local Delivery queue generally mean? - This indicates a performance issue or outage on the local server. Reasons could be slowness in consulting AD, slowness in handing messages off to local delivery or SMTP delivery. It could also be databases being dismounted or a lack of disk space.
What are the standard port numbers for SMTP, POP3, IMAP4, RPC, LDAP and Global Catalog? - SMTP – 25, POP3 – 110, IMAP4 – 143, RPC – 135, LDAP – 389, Global Catalog - 3268
Name the process names for the following: System Attendant? – MAD.EXE, Information Store – STORE.EXE, SMTP/POP/IMAP/OWA – INETINFO.EXE
What is the maximum amount of databases that can be hosted on Exchange 2003 Enterprise? - 20 databases. 4 SGs x 5 DBs.
What are the disadvantages of circular logging? - In the event of a corrupt database, data can only be restored to the last backup.
These questions were sent in from IBM. They discuss various telecom and networking topics.
OSPF
Describe OSPF in your own words.
OSPF areas, the purpose of having each of them
Types of OSPF LSA, the purpose of each LSA type
What exact LSA type you can see in different areas
How OSPF establishes neighboor relation, what the stages are
If OSPF router is stucked in each stage what the problem is and how to troubleshoot it
OSPF hierarchy in the single or multi areas. Cool OSPF behavior in broadcast and nonbroadcast
Draw the diagram of typical OSPF network and explain generally how it works, DR, BDR, election, ASBR, ABR, route redistribution and summarization
More interview questions »
Posted in: Networking Comments(0)
More than 200 CCNA questions
As system administrator, you type “debug ipx sap” and receive the following lines as part of the IOS response: type 0×4, “HELLO2″, 199.0002.0003.0006 (451), 2 hops type 0×4, “HELLO1″, 199.0002.0003.0008 (451), 2 hops What does “0×4″ signify?* That is a Get Nearest Server response.* That it is a General query.* That it is a General response.* That it is a Get Nearest Server request.Correct answer: A
To monitor IP igrp traffic, you can use “debug IP igrp transaction” or “debug IP igrp events”. How do you display information about IPX routing update packets?* debug routing* debug ipx transaction* debug ipx routing activity* debug ipx eventsCorrect answer: C
More interview questions »
Posted in: Networking Comments(7)
Networking questions
What is a default gateway? - The exit-point from one network and entry-way into another network, often the router of the network.
How do you set a default route on an IOS Cisco router? - ip route 0.0.0.0 0.0.0.0 x.x.x.x [where x.x.x.x represents the destination address]
What is the difference between a domain local group and a global group? - Domain local groups grant permissions to objects within the domain in which the reside. Global groups contain grant permissions tree or forest wide for any objects within the Active Directory.
What is LDAP used for? - LDAP is a set of protocol used for providing access to information directories.
What tool have you used to create and analyze packet captures? - Network Monitor in Win2K / Win2K3, Ethereal in Linux, OptiView Series II (by Fluke Networks).
How does HSRP work?
What is the significance of the IP address 255.255.255.255? - The limited broadcast address is utilized when an IP node must perform a one-to-everyone delivery on the local network but the network ID is unknown.
What is Active Directory schema?
What are the domain functional level in Windows Server 2003?
What are the forest functional level in Windows Server 2003?
What is global catalog server?
How we can raise domain functional & forest functional level in Windows Server 2003?
Which is the deafult protocol used in directory services?
What is IPv6?
What is the default domain functional level in Windows Server 2003?
What are the physical & logical components of ADS
In which domain functional level, we can rename domain name?
What is multimaster replication?
What is a site?
Which is the command used to remove active directory from a domain controler?
How we can create console, which contain schema?
What is trust?
What is the file that’s responsible for keep all Active Directory database?
Posted in: Networking, Windows
51 Responses to “Windows sysadmin interview questions”
Aneesh Says: March 29th, 2006 at 11:49 pm
The Active Directory schema contains formal definitions of every object class that can be created in an Active Directory forest it also contains formal definitions of every attribute that can exist in an Active Directory object.Active Directory stores and retrieves information from a wide variety of applications and services. So that it can store and replicate data from a potentially infinite variety of sources, Active Directory standardizes how data is stored in the directory. By standardizing how data is stored, the directory service can retrieve, update, and replicate data while ensuring that the integrity of the data is maintained.
kiran Says: May 15th, 2006 at 11:46 pm
1) Schema master is a set of rules which is used to define the struture of active directory. It contains definitions of all the objects which are stored in AD. It maintains information and detail information of objects.
2) If there are many organisational units and to implement policy on all OUś we use Domain level policy.
3)
4) Global Catalog Server maintains full information about its own domain and partial information about other domains. It is a forest wide role.
12) Sites: one or more well-connected highly reliable and fast TCP/IP subnets. A site allows administrator to configure active directory access and replication topology to take advantage of the physical network.
13) dcpromo to add/remove active directory but first ADC should be removed before DC if we want to remove DC first then check this server is last domain controller in domain.
16) I think the answer for this is schema master.
Pinkesh Says: June 3rd, 2006 at 8:00 am
Can you explain us briefly Archeitecture of Windows 2000/2003?
Pinkesh Says: June 3rd, 2006 at 8:01 am
What are main differences in Windows NT and Windows 2000 Archeitecture ?
Muniraj Says: June 24th, 2006 at 2:41 am
HII was just googling for Interview FAQ’s i got this URL as first choiceit is really dream come true situation for me because readily all possible question’s and answers are given.
Please send me if u have any FAQ on Exchnage Related.
Thanx and regardsMuniraj
shaik Says: June 29th, 2006 at 2:31 am
HII was just googling for Interview FAQ’s i got this URL as first choiceit is really dream come true situation for me because readily all possible question’s and answers are given.
Please send me if u have any FAQ on Exchnage Related.
Thanx and regards
shaik
SUVENDU Says: August 15th, 2006 at 11:08 pm
4.What is global catalog server?
A global catalog server is a domain controller it is a master searchable database that contains information about every object in everydomain in a forest. The global catalog contains a complete replica of allobjects in Active Directory for its host domain, and contains a partial replicaof all objects in Active Directory for every other domain in the forest.It have two important functions:i)Provides group membership information during logon and authenticationii)Helps users locate resources in Active Directory
SUVENDU Says: August 15th, 2006 at 11:08 pm
4.What is global catalog server?
A global catalog server is a domain controller it is a master searchable database that contains information about every object in everydomain in a forest. The global catalog contains a complete replica of allobjects in Active Directory for its host domain, and contains a partial replicaof all objects in Active Directory for every other domain in the forest.It have two important functions:i)Provides group membership information during logon and authenticationii)Helps users locate resources in Active Directory
SUVENDU Says: August 15th, 2006 at 11:11 pm
13 Which is the command used to remove active directory from a domain controler?
ANS ” DCPROMO ” in command prompt
SUVENDU Says: August 15th, 2006 at 11:29 pm
10. In which domain functional level, we can rename domain name?
All domain controllers must be running Windows Server 2003, and the Active Directory functional level must be at the Windows Server 2003.Yes u can rename the domain in windows server 2003
irfan Says: September 1st, 2006 at 1:19 am
User(s) are complaining of delays when using the network. What would you do?
shaik Says: September 3rd, 2006 at 12:24 pm
hi
15.NTDS.DIT14. we have to open the register to see the schema master fsmo roleregser 32 schmamgmt.9.Physical computers,sites,dcLogical user,o.us, etc….6.Light wait directory Access Protocal (ldap)5. What ever changes done in D.c(domain Controlers) will effect at A.Dwe can call it as multimaster .
Kumar Ken Says: September 13th, 2006 at 3:53 pm
Hi15. To allow users in one domain to access resources in another, AD uses trust. Trust is automatically produced when domains are created. The forest sets the default boundaries of trust, not the domain, and implicit trust is automatic. As well as two-way transitive trust, AD trusts can be shortcut (joins two domains in different trees, transitive, one- or two-way), forest (transitive, one- or two-way), realm (transitive or nontransitive, one- or two-way), or external (nontransitive, one- or two-way) in order to connect to other forests or non-AD domains. AD uses the Kerberos V5 protocol, although NTLM is also supported and web clients use SSL/TLS.
11.Multi-master replication is a method of replication employed by databases to transfer data or changes to data across multiple computers within a group. Multi-master replication can be contrasted with a master-slave method (also known as single-master replication).
7.Internet Protocol version 6 (IPv6) is a network layer IP standard used by electronic devices to exchange data across a packet-switched internetwork. It follows IPv4 as the second version of the Internet Protocol to be formally adopted for general use.
hongsinh Says: September 19th, 2006 at 3:00 am
What are the domain functional level in Windows Server 2003?
Sarith Says: September 22nd, 2006 at 3:26 am
Please check this link :) this will help youh**p://technet2.microsoft.com/WindowsServer/en/library/b3674c9b-fab9-4c1e-a8f6-7871264712711033.mspx?mfr=true
Naresh Nimmagadda Says: October 13th, 2006 at 9:06 am
ip v6it ia a 128 bit size addresshere we can see total 8 ocatates each octate size is 16 bits superated with “:”it is in hexa decimal formatethese 3 types1.unicast address2.multicast address3.anycast addressloopback address of ip v6 is ::1
Ramanand Says: November 27th, 2006 at 5:00 am
What is mean by dns,dhcp.?what is maen different between hub and switch ?what is meam by brodcast id?what is mean by loop back id?what is mean by schema ?what is mean by master searchable directory
Srikanth Says: December 8th, 2006 at 6:08 am
10. In which domain functional level, we can rename domain name?
The System Properties dialog box can also be used to rename a domain controller, and it does not require the functional level to be raised to Windows Server 2003.
Renga Raju Says: December 13th, 2006 at 11:43 pm
1.What is Rsop ?Resultant set of policy is provid to make policy modification and trouble shooting easier. Rsop is the query object it has two mode 1.logging mode: Polls existing policies and the reports the result of the query. 2.Planning mode: The questins ask about the planned policy and the report the result of the quer.2.What is the concept for authoritative and nonauthoritative restoration?1. Non-authoriative restore: which accept the entries from other domain controller after the restoed data.2.Authoritative: Not accept the entries from other domain controller.3.What is the ntds.tit file default size?40 mb
niraj Says: December 14th, 2006 at 5:28 am
13 Which is the command used to remove active directory from a domain controler?
ANS i think ” DCPROMO ” in command prompt .
11.What is multimaster replication?Ans. It is also known as single-master replication.Multi-master replication is a method of replication employed by databases to transfer data or changes to data across multiple computers within a group. Multi-master replication can be contrasted with a master-slave method.
Sachin Says: February 19th, 2007 at 6:54 am
What is Multimaster replication?
In addition to storing primary zone information in Dns we can also store it in active directory as active directory object.This integrates Dns with active directory in order to take advantage of active directory features
The benefits are1 zone can be modified from any domain controller within the domain and this information is automatically updated or replicated to all the other domain controllers along with the active directory replication.This replication is said to be multimaster replication.2.We no longer face the standard dns server drawbacks.
In standard dns server only the primary server can modify the zone and then replicate the changes to other domain controllers(It was in windows NT4 before).But when Dns gets integrated with AD .Zone can be modified and replicated from any domain controller.
3.Fault tolerance4.Security
You can prevent access to any updates to zone or individual record preventing insecure dynamic updates.
Unnikrishnan Says: February 24th, 2007 at 7:08 am
13 Which is the command used to remove active directory from a domain controler?
ANS : DCPROMO
Unnikrishnan Says: February 24th, 2007 at 7:10 am
11 What is multimaster replication?
The two technologies in DFS are as follows:
DFS Replication. New state-based, multimaster replication engine that is optimized for WAN environments. DFS Replication supports replication scheduling, bandwidth throttling, and a new byte-level compression algorithm known as remote differential compression (RDC).
DFS Namespaces. Technology that helps administrators group shared folders located on different servers and present them to users as a virtual tree of folders known as a namespace. DFS Namespaces was formerly known as Distributed File System in Windows 2000 Server and Windows Server 2003.
pavan Says: February 28th, 2007 at 2:39 pm
hi1)What is system boot process in windows and linux.2)how the hardware interact with OS.3)what is paging.
Thanks
Salman MW Says: March 7th, 2007 at 3:56 pm
8. The default domain functional level in Windows Server 2003 is “Windows 2000 Mixed”
10. We can rename domain name in “Windows Server 2003″ functional level
William Wood Says: March 13th, 2007 at 4:59 am
16. NTDS.dit
jagjit singh Says: March 26th, 2007 at 11:16 am
for removing active directory the command line is
dcpromo /forceremoval
Sanjay Patel Says: March 30th, 2007 at 1:24 pm
Removing Active Directory:1. If we want to remove Active Directory then we willuse command……DCPROMO2. If some one deleted parent domain and we want toremove from child domain then we will use command…DCPROMO /FORCEREMOVALNote: - we should not remove parent domain first. weshould start from bottom means child domainand after that it’s parent and so on.
Sanjay Patel Says: March 30th, 2007 at 1:53 pm
1. DNS(Domain Name Service):—————————-It’s mainly used to resolve from host name(FQDN-Fully Qualified Domain Name) to IP address and IP address to host name.DNS mainly used in Internet. DNS devide in form of hierarchical.
2. DHCP(Dynamic Host Configuration Protocol):———————————————DHCP use for provide IP address dnamically to client machine. If that client not able to find DHCP server then client machine will go for APIPA(We have range for APIPA which is 169.254.0.1-169.254.255.254).
3. HUB and SWITCH:——————Switch is expencive than hub. If more then one user try to send packet at a time collision will occure but in switch we can send. Switch is full duplex. Maximum bandwidth is 100 Mhz and that bandwidth is shared by all of the PC’s connected to the hub. Data can be sent in both directions simultaneously, the maximum available bandwidth is 200 Mbps, 100 Mbps each way, and there are no other PC’s with which the bandwidth must be shared.
Sanjay Patel Says: March 30th, 2007 at 1:55 pm
3. HUB and SWITCH:——————Switch is expencive than hub. If more then one user try to send packet at a time collision will occure but in switch we can send. Switch is full duplex. In hub Maximum bandwidth is 100 Mhz and that bandwidth is shared by all of the PC’s connected to the hub. In switch data can be sent in both directions simultaneously, the maximum available bandwidth is 200 Mbps, 100 Mbps each way, and there are no other PC’s with which the bandwidth must be shared.
Zahed Says: March 30th, 2007 at 2:11 pm
Hi,1.What is differnece between router and routing?2.What is dynamic routing and Static routing?
Sanjay Patel Says: March 31st, 2007 at 12:50 pm
1. Difference between Router and Routing: -——————————————-Router: -———Router is a device which is used to connect different network. A device or setup that finds the best route between any two networks, even if there are several networks to traverse. Like bridges, remote sites can be connected using routers over dedicated or switched lines to create WANs.Routing: -———-Process of delivering a message across one or more networks via the most appropriate path.
2. Dynamic Routing and Static Routing: -—————————————-Dynamic routing performs the same function as static routing except it is more robust. Static routing allows routing tables in specific routers to be set up in a static manner so network routes for packets are set. If a router on the route goes down the destination may become unreachable. Dynamic routing allows routing tables in routers to change as the possible routes change. There are several protocols used to support dynamic routing including RIP and OSPF
william wood Says: April 9th, 2007 at 5:32 am
The schema is the component of the Active Directory directory service that defines all the objects and attributes that the directory service uses to store data. You can combine some objects in the schema to create more-complex definitions if objects of greater complexity are required. You can also add new definitions to the schema to support new types of objects in the directory.
Zahed Says: April 18th, 2007 at 1:45 pm
Hi, i want to know to total process to migrate from Windows NT server to Windows 2000 server.
What are all the process will done when we start server tell me briefly which file work for which process.
Thnaks warm Regards,Zahed.
om Says: April 30th, 2007 at 11:12 am
The schema is the component of the Active Directory directory service that defines all the objects and attributes that the directory service uses to store data. You can combine some objects in the schema to create more-complex definitions if objects of greater complexity are required. You can also add new definitions to the schema to support new types of objects in the directory.
omraj Says: April 30th, 2007 at 11:13 am
Dynamic routing performs the same function as static routing except it is more robust. Static routing allows routing tables in specific routers to be set up in a static manner so network routes for packets are set. If a router on the route goes down the destination may become unreachable. Dynamic routing allows routing tables in routers to change as the possible routes change. There are several protocols used to support dynamic routing including RIP and OSPF
vijay Says: May 25th, 2007 at 7:22 am
The four domain functional levels are:
Windows 2000 MixedWindows 2000 NativeWindows Server 2003 InterimWindows Server 2003
Windows 2000 Mixed
When you configure a new Windows Server 2003 domain, the default domain functional level is Windows 2000 mixed.Under this domain functional level, Windows NT, 2000, and 2003 domain controllers are supported. However,certain features such as group nesting, universal groups, and so on are not available.
Windows 2000 NativeUpgrading the functional level of a domain to Windows 2000 Native should only be done if there areno Windows NT domain controllers remaining on the network. By upgrading to Windows 2000 Native functional level,additional features become available including: group nesting, universal groups, SIDHistory, and the ability to convertsecurity groups and distribution groups.
Windows Server 2003 InterimThe third functional level is Windows Server 2003 Interim and it is often used when upgrading fromWindows NT to Windows Server 2003. Upgrading to this domain functional level provides support forWindows NT and Windows Server 2003 domain controllers. However, like Windows 2000 Mixed, it does not provide new features.
Windows Server 2003The last functional level is Windows Server 2003. This domain functional level only provides support forWindows Server 2003 domain controllers. If you want to take advantage of all the features included withWindows Server 2003, you must implement this functional level. One of the most important features introducedat this functional level is the ability to rename domain controllers
Annveer N. Halkood Says: July 29th, 2007 at 10:58 pm
what are the types of name resolution?
how name resolution will take place?
what are the Groups?
what is DHCP Relay agent?
Thyagu Says: September 18th, 2007 at 7:48 pm
1.Active Directory schema is collection of object class and attributes.Eg user is an object and its having alot attributes such as first name ,last name etc…It present in only one domain in a forest,schema master is having the ability to update the changes in the Active directory schema.Schema Administrator only can access and edit the schema.
you cannot see the AD schema when you installed AD (dcpromo).
You need to run the registry file for schema in cmd mode :regsvr32.dll schmmgmt
Then you can see the Add -snap in wizard in mmc console ,there you can..
2.the domain functional level in Windows Server 2003
Domain fuctional level support only the windows domain controllers not client level o/s.
They are four:windows 2000 mixed(by default) supports- win nt,win 2000,win2003.Windows 2000 native- supports- win 2000 ,win 2003Windows 2003 interim- supports ->win NT,win 2003Windows 2003 - supports-win 2003 only
3.forest functional level in Windows Server 2003There are threewindows 2000 mixed supports- win nt,win 2000,win2003.Windows 2000 native- supports- win 2000 ,win 2003Windows 2003 - supports-win 2003 only
4.Global CatalogIt is a searchable database Enginee.It is used to search the objects in a forest.In 2003 ,Universal Group caching membership is available for speedy logon across domain. Port no:3268,3269It is also taking part of AD replication.
Sorry guys ,going out now… i wll cont…later
Thyagu Says: September 19th, 2007 at 5:04 pm
5.How we can raise domain functional & forest functional level in Windows Server 2003?
AD users and computers–>domain functional level->choose DFL as per your environment.
AD Domain and Trust–>Forest functional level–>choose FFL as would your environment.
Note:once you have change the DFL and FFL,cannot be revert.
6.the deafult protocol used in directory services?LDAP.
8.Already answered
9.What are the physical & logical components of ADS
Physical->sites,domain controller
Logical ->Forest,domain,tree,ou
10.In which domain functional level, we can rename domain name
Windows 2003 dfl,you can rename the domain.
Note:Not recommended to rename the domain by Microsoft itself.You need to follow up the proper procedure to prevent the further issue.Renaming is simple,but forecast issue is lot.
11.multi-master replication
Whenever a change occurs to any object within an Active Directory domain, that change is replicated automatically to all domain controllers within the domain. This process is called multi-master replication. Multi-master replication does not happen instantly across all servers simultaneously. Rather, it is a controlled process where each domain controller peer is updated and validated in a logically controlled procedure.
12.Site:
Site is one or more IP subnets.It contains connection objects and computer objects and mainly used for AD replication.
13.Dcpromo, the command used to remove active directory from a domain controler
14.Already answered.
15.Trust is relationship,between forest,domain.
16 NTDS.dit is the file that’s responsible for keep all Active Directory database.
I have answered almost question.please let me if my answer is wrong.
PREM Says: September 26th, 2007 at 7:12 am
The schema is the component of the Active Directory directory service that defines all the objects and attributes that the directory service uses to store data. You can combine some objects in the schema to create more-complex definitions if objects of greater complexity are required. You can also add new definitions to the schema to support new types of objects in the directory.
MAK Says: October 10th, 2007 at 3:01 pm
What is a default forest functionl level when you install the root domain controller ?
Raj Narayan Says: October 23rd, 2007 at 9:24 am
Hi,Can you pleas answer my query1.How to Export the Ad data in Excel.Specially Tabs Like (General,Account,Exchange Advance,Security,Members of )Without any 3rd party software.
2. Suppose i have deleted any object from Ad but after 2-3 days i want back that object..What is the process to restore the deleted Ad object.
Raj Narayan Says: November 22nd, 2007 at 4:55 am
Hi,Can anyone give me the answer of the mention Questions:1. Windows server 2008 is actual which version of Windows server ?2. Explain NAP in Windows Server 20083. How 1 can implement IP verison 6 using Windows Server 2008?4. What are the enhancements in Terminal server which comes with Win2k8 ?5. Which version of IIS comes with Windows server 2008?6. What is the new feature included in Windows Server 2008 which can lock entire hard disk drive?7. How easy it is to combine Windows Server 2008 os with physical networking & security appliances?8. What are the certifications available for Windows 2008 track?9. What is MCP member site and whats advantage of it ?10. What is TechNet subscription and what indivisual get by subscribing to TechNet?
Regards,Raj Narayan
Murali Chowdary Says: January 25th, 2008 at 8:36 am
A global catalog server is a domain controller it is a master searchable database that contains information about every object in everydomain in a forest. The global catalog contains a complete replica of allobjects in Active Directory for its host domain, and contains a partial replicaof all objects in Active Directory for every other domain in the forest.
Prasath Jayabal Says: March 3rd, 2008 at 5:34 am
What is DHCP relay agent?
If you have two or more subnet,you need to configure more DHCP server in each subnet instead of place DHCP server ,we can configure DHCP relay angent wherever you want.
Note:Minimum one DHCP server on your network
Prasath Jayabal Says: March 3rd, 2008 at 5:42 am
What is mean by dns,dhcp ?
DNS : it is Domain name system ,this is used to reslove the IP address to site name and, site name to IP address
DHCP: It is dynamic host configuration protocol,It is using to distribute the IP to all client systems in a network.
Prasath Jayabal Says: March 3rd, 2008 at 5:52 am
what is maen different between hub and switch ?
Hub :It is place of convergence where data arrives from one system ,it will forward the message to all ,it is a layer one device.
It comes under physical layer
Switch : It is place of convergence where data arrives from one system first i will see the source MAC (Media Access Contol) and destination MAC and it will forward to Particular destination MAC ID.
It is layer two device(Data Link Layer)
Prasath Jayabal Says: March 3rd, 2008 at 6:12 am
what is meam by brodcast id?It will forward the message to all system in a network (255.255.255.255).
Example : This is my Ip address 192.168.1.1/30let we find out the subnet,host address,broadcast address ?
Subnet will be 255.255.255.252My valued host address is 192.168.1.5 to 192.168.1.6My broadcast address will 192.168.1.7
Prasath Jayabal Says: March 3rd, 2008 at 6:20 am
what is mean by loop back id?
It is local host address using this we can check the TCP/IP protocol stack ,special to check the network card (127.0.0.1).
Prasath Jayabal Says: March 3rd, 2008 at 6:24 am
what is mean by schema ?
Windows Server 2000/2003 Active Directory uses a database set of rules is called Schema
Responses to “Network developer interview questions”
mala Says: October 27th, 2005 at 4:34 am
What is TCP window sizing
rrovegno Says: November 16th, 2005 at 12:10 am
1. How does TCP handshake work? Transmission Control Protocol/Internet Protocol. There are 3 steps.1. Local device sends sequence number and maximum segment size.2. Destination device responds by sending its sequence number and maximum segment size back to local device.3. Local device acknowledges receipt of the sequence number and segment size information.
2. How does SSL handshake work? Secure Sockets Layer. There are 4 steps.1. Browser checks the certificate to make sure that the site you are connecting to is the real site and not someone intercepting.2. Determine encryption types that the browser and web site server can both use to understand each other.3. Browser and Server send each other unique codes to use when scrambling (or encrypting) the information that will be sent.4. The browser and Server start talking using the encryption, the web browser shows the encrypting icon, and web pages are processed secured.
3. What is the difference between passive FTP and active FTP?FTP is an unusual protocol in that it uses two ports, one for commands and the other for data. (This is one of the reasons it is superior to HTTP for transferring large files.) Active FTP was invented first. The client initiates a connection on the server’s command port. The server then initiates a connection with the client from its data port. In Passive FTP, the client initiates both connections with the server, which remains “passive”.Active FTP may cause problems if your client is behind a firewall. From the firewall’s point of view, the FTP server that is trying to initiate a connection with your client looks like an intruder and is usually blocked. This is why many users have difficulty using FTP to download files from behind a firewall.Passive FTP solves this problem, but creates other problems, notably where FTP server security is concerned. The server must listen on a large number of ports. This requires the firewall to let a lot of unqualified traffic through. Most firewall administrators do not like this.As a rule, you do not need to be concerned about passive and active FTP unless you administer an FTP server or a firewall. If you experience difficulty using your FTP client from behind a firewall, this is likely the reason. Perhaps you should discuss the matter with your firewall administrator.
4. What is the difference between socket and session?1. An SSL session is a mechanism through which connections can be established by re-using previously negotiated handshakes.2. A socket is one endpoint of a two-way communication link between two programs running on the network. A socket is bound to a port number so that the TCP layer can identify the application that data is destined to be sent.
5. How does network management station work? Network management stations execute management applications which monitor and control network elements. Network elements are devices such as hosts, gateways, terminal servers, and the like, which have management agents responsible for performing the network management functions requested by the network management stations. The Simple Network Management Protocol (SNMP is used to communicate management information between the network management stations and the agents in the network elements. There are a few network management features that may be used to provide network monitoring for this advisory.1. Device Availability Monitoring2. SNMP MIB object monitoring3. Cisco Service Assurance Agent (Cisco SAA)4. RMON Alarm and Events5. Event-MIB6. CiscoWorks RME Network Show Commands and CLI scripting
6. What are the different phases in VPN establishment? Successful VPN establishment consists of two levels of SA’s known as phases. Phase 1 authentication establishes session keys. Using the Xauth feature, the client waits for a “username/password” challenge after the IKE Phase 1 SA has been established. When the end user responds to the challenge, the response is forwarded to the IPsec peers for an additional level of authentication completing Phase 2.1. Phase 1 of a 2 phase VPN tunnel establishment process. Phase 1 negotiates the security parameter agreement.2. Phase 2 of 2 phase VPN tunnel establishment process. Phase 2 uses the agreed parameters from Phase 1 to bring the tunnel up.
7. How does DH (deffie helman) work? Diffie-Hellman key agreement was invented in 1976 during a collaboration between Whitfield Diffie and Martin Hellman and was the first practical method for establishing a shared secret over an unprotected communications channel. Based on Ralph Merkle’s public key cryptosystem. Public key cryptography is a form of cryptography which generally allows users to communicate securely without having prior access to a shared secret key, by using a pair of cryptographic keys, designated as public key and private key, which are related mathematically.
8. What is TCP window sizing? The window size is the maximum number of bytes of data that can be transmitted in one segment. Increasing the window size for a TCP-based file transfer would increase throughput until the slowest link in the path saturates. It would be preferable to have a window size appropriate to the size of the link. There would be less buffering, the ACKs would return more quickly and more of the bandwidth would be used. Ideally you are looking for a Window Size >= Bandwidth * RTT.
9. What is MTU? Maximum Transmission Unit. The greatest amount of data or “packet” size that can be transferred in one physical frame on a network. This packet also contains the header and trailer information, which are like addresses for each packet that are required by the routers on the network.
harikrishna Says: June 19th, 2006 at 2:37 am
i have doughts in snmp1)what is mib,where they used2)whai oids why they used
Gilli Says: May 7th, 2007 at 6:38 am
Hari,
To answer your queries.
1. What is MIB..MIB is Management Information Base - just a database which contains the information of all the managed objects of the particular device.
2. What is OID ….A MIB contains many object what are know as OID (Object Identifier) to identify that particular object.
eg: RFC1213-MIB have many objects which gives you the basic information of the device, like system name, system location etc.. sysName, sysLocation are all known as OID.
karthikeyan.m(TETCOS) Says: May 23rd, 2007 at 10:47 pm
What is the difference betwenn Reno and new Reno algorithm in TCP?
Desi Dimova Says: October 19th, 2007 at 8:03 am
1. How does TCP handshake work? It’s a 3 way handshake. The client sends a SYN packet to the server. The server replies with a SYN packet and acknowledges the client’s SYN packet by sending an ACK packet. The client acknowledges the SYN packet sent by the server. SYN-SYN/ACK-SYN.2. How does SSL handshake work? The SSL handshake protocol helps determine the session key, a symmetrical key used to encrypt data after a connection has been established. The protocol sends browser’s SSL version number, encryption settings, and other crypto information to the remote host. The remote host sends back its own SSL number and cipher settings back to the client. The server may verify the client’s certificate. The client verifies the server’s CA to make sure the server is authentic. The client creates a premaster secret, a SSL session encrypted using the server’s public key and sent to the server. When the server receives the encrypted premaster secret, the server uses it to verify the client’s identity optionally. Then the premaster secret is decrypted and used to determine the session key.3. What is the difference between passive FTP and active FTP?With active FTP, a client connects to server’s command port 21 from any port n > 1023. Server responds from port 21 to client’s control port. The server initiates a connection from the server data port 20 to the client’s data port n+1. Client sends ACK to the server’s data port. In passive mode, both connections are initiated by the client. The client opens 2 random ports locally, n>1023 and n+1, sending PASV to the server’s command port 21. The server opens port m >1023 and then the client initiates the connection from port N+1 to the server’s data port m.
One Response to “Some PC and networking questions”
rrovegno Says: November 16th, 2005 at 12:07 am
1. Workers can not print from the printer, there user logon are correct and are allowed to print from that printer in active directory. How would you resolve this issue?This is vague and could have multiple responses. Here are a few.1. Verify printer is set as default.2. Verify users have local privileges set properly to print.3. Is print server delivering correct drivers?4. Is local naming convention for printer correct?5. If pre Win2000 workstation, naming convention must be less than 12 characters.6. Make sure no viruses present. Some Viruses can shut down IPC shares and printing services.
2. What is the difference between hub and switch?A hub is not smart and allows all connected nodes/networks to communicate with each other. You a are limited to 10/100Mb half duplex operation on a hub. To hook two hubs togethor you would use a crossover cable. Most hubs also have a crossover port which will allow you to use a regular cable to hook two hubs/switches togethor.A switch on the other hand can be an OSI Model layer 2 or 3 device. A switch forwards information by mac address. The mack address is a hard coded alpha numeric number that is used to identify a network adapter. Whenever a call is made to another computer, the switch looks in it’s mac address table and see’s if this node is directly connected to the switch by looking it up in the mac address database. If it is not, however, if forwards it down all switch ports looking for the destination. A layer 2 switch is even smarter. It can actually route traffic based on it’s layer 3 address. It will look up the destination in it’s mac address table first, if does not find it, it will forward it by looking at the route table and send it on it’s merry way to it’s destination. A switch will also allow you to set a switch port at 10/100Mb full duplex to increase node communication speed.Hubs should be used in smaller networking environments and switches should be used whenever you need to segment your network or you are having problems with collisions on your ethernet network. If you have over a 100 clients in a location, it’s a good idea to uses switches.If you intend on using them both, you would normally use the switch as the backbone and the hubs as connections. Each hub would have it’s own switch port on the switch. I normally reccommend that if your going to use a switch in place of a hub then get rid of all your hubs and move completely to switches. This will allow for increased network performance, a more structured segmenting of the network, and better traffic control. Hubs, since they are not smart, send broadcasts down all ports unlike a switch, which can cause performance degradation on the network. This causes all clients/nodes to have to respond to the broadcast.
3. Your hard drive is partitioned as follows: 8 gigs for OS drive C, 8 gigs for Hot Swappable drive D and rest is free as drive E. Your drive C crashes, how would you reboot your system without installing a new operating system?This is also vague and poorly put together. It is represented as a single HDD but the reference to Hot Swappable would infer a secondary device. Perhaps he misunderstands the technology. As it is unclear, this could have multiple responses as well. Here are a few.1. It is hard to tell how many physical disks there are based on the description? If it is hardware related and the first drive has literally crashed physically (head crash for example) the second drive may have an OS. As it is the only drive referred to as Hot Swappable, you may be able to remove the drive that crashed and change jumper settings on the second drive making it the primary drive. Then it will reboot provided it has an OS.2. If this is a single drive with an NT OS and it is setup with multiple boot partitions, you may be able to boot to one of the other partitions.3. You may be able to use the original OS CD or floppy disk and repair the OS installation. This is provided the HDD is ok and the partition is the only problem.4. If Hot Swappable means a secondary physical drive, where the first partition is mirrored, then down the computer and swap the drives. Re-power up.4. Your computer gives you “non-disk error” before you log on what would you do to make your computer work?Again there are potentially multiple scenarios here.1. Make sure a non OS floppy is not present in A:2. Make sure hard drive has not crashed.3. Based on OS, boot from floppy and re-sys disk, or use CD to repair OS.
What is a firewall?
Describe, genrally, how to manage a firewall
What is a Denial of Service attack?
What is a “spoofed” packet?
What is a SYN Flood?
What do you do if you are a victim of a DoS?
What is GPG/PGP?
What is SSH?
What is SSL? How do you create certificates?
What would you do if you discovered a UNIX or Network device on your network has been compromised?
What would you do if you discovered a Windows system on your network has been comrpromised?
What is DNS Hijacking?
What is a log host?
What is IDS or IDP, and can you give me an example of one?
Why are proxy servers useful?
What is web-caching?
Posted in: Networking
11 Responses to “Security interview questions for network admin”
anju Says: February 28th, 2006 at 4:14 pm
A firewall is simply a program or hardware device that filters the information coming through the Internet connection into your private network or computer system. If an incoming packet of information is flagged by the filters, it is not allowed through.
Firewalls use one or more of three methods to control traffic flowing in and out of the network:
* Packet filtering - Packets (small chunks of data) are analyzed against a set of filters. Packets that make it through the filters are sent to the requesting system and all others are discarded.* Proxy service - Information from the Internet is retrieved by the firewall and then sent to the requesting system and vice versa.* Stateful inspection - A newer method that doesn’t examine the contents of each packet but instead compares certain key parts of the packet to a database of trusted information. Information traveling from inside the firewall to the outside is monitored for specific defining characteristics, then incoming information is compared to these characteristics. If the comparison yields a reasonable match, the information is allowed through. Otherwise it is discarded.
Ranjha Singh Says: November 3rd, 2006 at 10:43 am
DNS Hijacking mean hijacker spoof the ip of any DNS query. Lets example. user send a DNS requset for YAHOO.com and Hijacker hijack this packet & answer on behalf of DNS and give the wrong IP Assres.
Ranjha Singh Says: November 3rd, 2006 at 10:52 am
SSL is Secure Socket Layer. CA Genrates the certificates.
SUNIL ARORA Says: November 3rd, 2006 at 11:02 am
Denial of Service attack means server or machine receive so many packets from the single or multiple network sources or spoofed resources so that its all resources will be used to in responce of those packets & after that it will hang or not responding. Then it will start to denial to its services.
bob saget Says: December 8th, 2006 at 2:29 pm
Why are you answering these questions people? These are questoins for a ‘job interview’ not for you to show off your clearly impeccable grasp of the english language.
virendra yadav Says: May 8th, 2007 at 6:37 am
. FireWall is nothing but it is used to avoid the unwanted trafic or unauthorised entry. The Firewall has 2 types 1. Hardware & 2.Software. Now the most familiar used firewall is PIX from the make of cisco. and other firewalls like nokia and so on..further… as a security measure it also depends on the network designer and implementer that how to use a Firewall mean to say the security measures like how to present the content filtering and Url filtering which type of firewall should be used and where to put it..20d3
Harish P Says: June 5th, 2007 at 7:32 pm
9). What is SSL? How do you create certificates?
Ans : SSL: Secure Sockets Layer, a protocol developed by Netscape for transmitting private documents via the internet. SSL works by useing a private key to encrypt data that`s transferred over the SSL connection. Both Netscape Navigator and Internet Explorer support SSL and many Web sites use the protocol to obtain confidential user information, such as credit card numbers. By convention, Web pages that require an SSL connection start with https: instead of http .
Naveen Says: July 2nd, 2007 at 6:35 am
(1)A firewall is simply a program or hardware device that filters the information coming through the Internet connection into your private network or computer system. If an incoming packet of information is flagged by the filters, it is not allowed through.
Sunil Reddy Says: July 26th, 2007 at 12:53 pm
What is a firewall?
Firewall is a device or a software which restricts the unauthorised accesses to and from the network……….Guys its that simple no need to beat around the bush
CheersSunil Reddy.MSecurity Consultant
deepak kajla Says: September 3rd, 2007 at 1:24 am
ssh=secure shell used for remotely logged in another clint systems through a linux administrator.
DPK Says: November 27th, 2007 at 2:50 am
SSH is a secure way of connecting to a Server or Remote host. This protocols replaces the Telnet applications.
SSH uses 3 different ways of authentications,
1. Preshared Key authentication2. Public/Private key authentication3. Host based authentication
SSHkeygen tool is used to generate Public and Private keys for a host.

Dot net interview questions

1. What is .NET?That's difficult to sum up in a sentence. According to Microsoft, .NET is a "revolutionary new platform, built on open Internet protocols and standards, with tools and services that meld computing and communications in new ways".A more practical definition would be that .NET is a new environment for developing and running software applications, featuring ease of development of web-based services, rich standard run-time services available to components written in a variety of programming languages, and inter-language and inter-machine interoperability.Note that when the term ".NET" is used in this FAQ it refers only to the new .NET runtime and associated technologies. This is sometimes called the ".NET Framework". This FAQ does NOT cover any of the various other existing and new products/technologies that Microsoft are attaching the .NET name to (e.g. SQL Server.NET).2. Does .NET only apply to people building web-sites?No. If you write any Windows software (using ATL/COM, MFC, VB, or even raw Win32), .NET may offer a viablealternative (or addition) to the way you do things currently. Of course, if you do develop web sites, then .NET haslots to interest you - not least ASP.NET.3. When was .NET announced?Bill Gates delivered a keynote at Forum 2000, held June 22, 2000, outlining the .NET 'vision'. The July 2000 PDC had anumber of sessions on .NET technology, and delegates were given CDs containing a pre-release version of the .NET framework/SDK and Visual Studio.NET.4. When was the first version of .NET released?The final version of the 1.0 SDK and runtime was made publicly available around 6pm PST on 15-Jan-2002. At the same time, the final version of Visual Studio.NET was made available to MSDN subscribers.5. What platforms does the .NET Framework run on?The runtime supports Windows XP, Windows 2000, NT4 SP6a and Windows ME/98. Windows 95 is not supported. Some parts of the framework do not work on all platforms - for example, ASP.NET is only supported on Windows XP and Windows 2000. Windows 98/ME cannot be used for development.IIS is not supported on Windows XP Home Edition, and so cannot be used to host ASP.NET. However, the ASP.NET Web Matrix web server does run on XP Home.The Mono project is attempting to implement the .NET framework on Linux.6. What languages does the .NET Framework support?MS provides compilers for C#, C++, VB and JScript. Other vendors have announced that they intend to develop .NET compilers for languages such as COBOL, Eiffel, Perl, Smalltalk and Python.7. Will the .NET Framework go through a standardisation process?From http://msdn.microsoft.com/net/ecma/: "On December 13, 2001, the ECMA General Assembly ratified the C# and common language infrastructure (CLI) specifications into international standards. The ECMA standards will be known as ECMA-334 (C#) and ECMA-335 (the CLI)."Basic terminology8. What is the CLR?CLR = Common Language Runtime. The CLR is a set of standard resources that (in theory) any .NET program can take advantage of, regardless of programming language. Robert Schmidt (Microsoft) lists the following CLR resources in his MSDN PDC# article:Object-oriented programming model (inheritance, polymorphism, exception handling, garbage collection)Security model, Type system , All .NET base classes, Many .NET framework classes, Development, debugging, and profiling tools, Execution and code managementIL-to-native translators and optimizers
9. What is IL?IL = Intermediate Language. Also known as MSIL (Microsoft Intermediate Language) or CIL (Common Intermediate Language). All .NET source code (of any language) is compiled to IL. The IL is then converted to machine code at the point where the software is installed, or at run-time by a Just-In-Time (JIT) compiler.10. What is C#?C# is a new language designed by Microsoft to work with the .NET framework. In their "Introduction to C#" whitepaper, Microsoft describe C# as follows: "C# is a simple, modern, object oriented, and type-safe programming language derived from C and C++. C# (pronounced C sharp) is firmly planted in the C and C++ family tree of languages, and will immediately be familiar to C and C++ programmers. C# aims to combine the high productivity of Visual Basic and the raw power of C++." Substitute 'Java' for 'C#' in the quote above, and you'll see that the statement still works pretty well :-).11. What does 'managed' mean in the .NET context?The term 'managed' is the cause of much confusion. It is used in various places within .NET, meaning slightly different things.Managed code: The .NET framework provides several core run-time services to the programs that run within it - for example exception handling and security. For these services to work, the code must provide a minimum level of information to the runtime. Such code is called managed code. All C# and Visual Basic.NET code is managed by default. VS7 C++ code is not managed by default, but the compiler can produce managed code by specifying a command-line switch (/com+).Managed data: This is data that is allocated and de-allocated by the .NET runtime's garbage collector. C# and VB.NET data is always managed. VS7 C++ data is unmanaged by default, even when using the /com+ switch, but it can be marked as managed using the __gc keyword.Managed classes: This is usually referred to in the context of Managed Extensions (ME) for C++. When using ME C++, a class can be marked with the __gc keyword. As the name suggests, this means that the memory for instances of the class is managed by the garbage collector, but it also means more than that. The class becomes a fully paid-up member of the .NET community with the benefits and restrictions that brings. An example of a benefit is proper interop with classes written in other languages - for example, a managed C++ class can inherit from a VB class. An example of a restriction is that a managed class can only inherit from one base class.12. What is reflection?All .NET compilers produce metadata about the types defined in the modules they produce. This metadata is packaged along with the module (modules in turn are packaged together in assemblies), and can be accessed by a mechanism called reflection. The System.Reflection namespace contains classes that can be used to interrogate the types for a module/assembly.Using reflection to access .NET metadata is very similar to using ITypeLib/ITypeInfo to access type library data in COM, and it is used for similar purposes - e.g. determining data type sizes for marshaling data across context/process/machine boundaries.Reflection can also be used to dynamically invoke methods (see System.Type.InvokeMember), or even create types dynamically at run-time (see System.Reflection.Emit.TypeBuilder).Assemblies13. What is an assembly?An assembly is sometimes described as a logical .EXE or .DLL, and can be an application (with a main entry point) or a library. An assembly consists of one or more files (dlls, exes, html files etc), and represents a group of resources, type definitions, and implementations of those types. An assembly may also contain references to other assemblies. These resources, types and references are described in a block of data called a manifest. The manifest is part of the assembly, thus making the assembly self-describing.An important aspect of assemblies is that they are part of the identity of a type. The identity of a type is the assembly that houses it combined with the type name. This means, for example, that if assembly A exports a type called T, and assembly B exports a type called T, the .NET runtime sees these as two completely different types. Furthermore, don't get confused between assemblies and namespaces - namespaces are merely a hierarchical way of organising type names. To the runtime, type names are type names, regardless of whether namespaces are used to organise the names. It's the assembly plus the typename (regardless of whether the type name belongs to a namespace) that uniquely indentifies a type to the runtime.Assemblies are also important in .NET with respect to security - many of the security restrictions are enforced at the assembly boundary. Finally, assemblies are the unit of versioning in .NET - more on this below.14. What is the difference between a private assembly and a shared assembly?Location and visibility: A private assembly is normally used by a single application, and is stored in the application's directory, or a sub-directory beneath. A shared assembly is normally stored in the global assembly cache, which is a repository of assemblies maintained by the .NET runtime. Shared assemblies are usually libraries of code which many applications will find useful, e.g. the .NET framework classes.Versioning: The runtime enforces versioning constraints only on shared assemblies, not on private assemblies.15. How do assemblies find each other?By searching directory paths. There are several factors which can affect the path (such as the AppDomain host, and application configuration files), but for private assemblies the search path is normally the application's directory and its sub-directories. For shared assemblies, the search path is normally same as the private assembly path plus the shared assembly cache.16. How does assembly versioning work?Each assembly has a version number called the compatibility version. Also each reference to an assembly (from another assembly) includes both the name and version of the referenced assembly.The version number has four numeric parts (e.g. 5.5.2.33). Assemblies with either of the first two parts different are normally viewed as incompatible. If the first two parts are the same, but the third is different, the assemblies are deemed as 'maybe compatible'. If only the fourth part is different, the assemblies are deemed compatible. However, this is just the default guideline - it is the version policy that decides to what extent these rules are enforced. The version policy can be specified via the application configuration file.Remember: versioning is only applied to shared assemblies, not private assemblies.Application Domains17. What is an Application Domain?An AppDomain can be thought of as a lightweight process. Multiple AppDomains can exist inside a Win32 process. The primary purpose of the AppDomain is to isolate an application from other applications.Win32 processes provide isolation by having distinct memory address spaces. This is effective, but it is expensive and doesn't scale well. The .NET runtime enforces AppDomain isolation by keeping control over the use of memory - all memory in the AppDomain is managed by the .NET runtime, so the runtime can ensure that AppDomains do not access each other's memory.18. How does an AppDomain get created?AppDomains are usually created by hosts. Examples of hosts are the Windows Shell, ASP.NET and IE. When you run a .NET application from the command-line, the host is the Shell. The Shell creates a new AppDomain for every application.AppDomains can also be explicitly created by .NET applications. Here is a C# sample which creates an AppDomain, creates an instance of an object inside it, and then executes one of the object's methods. Note that you must name the executable 'appdomaintest.exe' for this code to work as-is.using System;using System.Runtime.Remoting;public class CAppDomainInfo : MarshalByRefObject{ public string GetAppDomainInfo(){ return "AppDomain = " + AppDomain.CurrentDomain.FriendlyName;} }public class App{ public static int Main(){ AppDomain ad = AppDomain.CreateDomain( "Andy's new domain", null, null );ObjectHandle oh = ad.CreateInstance( "appdomaintest", "CAppDomainInfo" );CAppDomainInfo adInfo = (CAppDomainInfo)(oh.Unwrap());string info = adInfo.GetAppDomainInfo();Console.WriteLine( "AppDomain info: " + info );return 0; } }1. What are the different modes for the sessionstates in the web.config file? Off Indicates that session state is not enabled.Inproc Indicates that session state is stored locally.StateServer Indicates that session state is stored on a remote server.SQLServer Indicates that session state is stored on the SQL Server.
2. What is smart navigation?When a page is requested by an Internet Explorer 5 browser, or later, smart navigation enhances the user's experience of the page by performing the following: • eliminating the flash caused by navigation. • persisting the scroll position when moving from page to page. • persisting element focus between navigations. • retaining only the last page state in the browser's history. Smart navigation is best used with ASP.NET pages that require frequent postbacks but with visual content that does not change dramatically on return. Consider this carefully when deciding whether to set this property to true.Set the SmartNavigation attribute to true in the @ Page directive in the .aspx file. When the page is requested, the dynamically generated class sets this property. 3. In what order do the events of an ASPX page execute. As a developer is it important to undertsand these events? 4. How would you get ASP.NET running in Apache web servers - why would you even do this? 5. What tags do you need to add within the asp:datagrid tags to bind columns manually 6. What base class do all Web Forms inherit from? System.Web.UI.Page 7. How can we create pie chart in asp.net? 8. Is it possible for me to change my aspx file extension to some other name?Yes.Open IIS->Default Website -> PropertiesSelect HomeDirectory tabClick on configuration buttonClick on add. Enter aspnet_isapi details (C:\WINDOWS\Microsoft.NET\Framework\v1.0.3705\aspnet_isapi.dll GET,HEAD,POST,DEBUG)
Open machine.config(C:\WINDOWS\Microsoft.NET\Framework\v1.0.3705\CONFIG) & add new extension under tag
9. What is AutoEventWireup attribute for ?
---WEBSERVICE & REMOTING---10. What is a WebService and what is the underlying protocol used in it?Why Web Services?Web Services are applications delivered as a service on the Web. Web services allow for programmatic access of business logic over the Web. Web services typically rely on XML-based protocols, messages, and interface descriptions for communication and access. Web services are designed to be used by other programs or applications rather than directly by end user. Programs invoking a Web service are called clients. SOAP over HTTP is the most commonly used protocol for invoking Web services.There are three main uses of Web services. 1. Application integration Web services within an intranet are commonly used to integrate business applications running on disparate platforms. For example, a .NET client running on Windows 2000 can easily invoke a Java Web service running on a mainframe or Unix machine to retrieve data from a legacy application. 2. Business integration Web services allow trading partners to engage in e-business leveraging the existing Internet infrastructure. Organizations can send electronic purchase orders to suppliers and receive electronic invoices. Doing e-business with Web services means a low barrier to entry because Web services can be added to existing applications running on any platform without changing legacy code. 3. Commercial Web services focus on selling content and business services to clients over the Internet similar to familiar Web pages. Unlike Web pages, commercial Web services target applications not humans as their direct users. Continental Airlines exposes flight schedules and status Web services for travel Web sites and agencies to use in their applications. Like Web pages, commercial Web services are valuable only if they expose a valuable service or content. It would be very difficult to get customers to pay you for using a Web service that creates business charts with the customers? data. Customers would rather buy a charting component (e.g. COM or .NET component) and install it on the same machine as their application. On the other hand, it makes sense to sell real-time weather information or stock quotes as a Web service. Technology can help you add value to your services and explore new markets, but ultimately customers pay for contents and/or business services, not for technology 11. Are Web Services a replacement for other distributed computing platforms?No. Web Services is just a new way of looking at existing implementation platforms. 12. In a Webservice, need to display 10 rows from a table. So DataReader or DataSet is best choice? Ans: WebService will support only DataSet. 13. How to generate WebService proxy? What is SOAP, WSDL, UDDI and the concept behind Web Services? What are various components of WSDL? What is the use of WSDL.exe utility?SOAP is an XML-based messaging framework specifically designed for exchanging formatted data across the Internet, for example using request and reply messages or sending entire documents. SOAP is simple, easy to use, and completely neutral with respect to operating system, programming language, or distributed computing platform.After SOAP became available as a mechanism for exchanging XML messages among enterprises (or among disparate applications within the same enterprise), a better way was needed to describe the messages and how they are exchanged. The Web Services Description Language (WSDL) is a particular form of an XML Schema, developed by Microsoft and IBM for the purpose of defining the XML message, operation, and protocol mapping of a web service accessed using SOAP or other XML protocol. WSDL defines web services in terms of "endpoints" that operate on XML messages. The WSDL syntax allows both the messages and the operations on the messages to be defined abstractly, so they can be mapped to multiple physical implementations. The current WSDL spec describes how to map messages and operations to SOAP 1.1, HTTP GET/POST, and MIME. WSDL creates web service definitions by mapping a group of endpoints into a logical sequence of operations on XML messages. The same XML message can be mapped to multiple operations (or services) and bound to one or more communications protocols (using "ports").The Universal Description, Discovery, and Integration (UDDI) framework defines a data model (in XML) and SOAP APIs for registration and searches on business information, including the web services a business exposes to the Internet. UDDI is an independent consortium of vendors, founded by Microsoft, IBM, and Ariba, for the purpose of developing an Internet standard for web service description registration and discovery. Microsoft, IBM, and Ariba also are hosting the initial deployment of a UDDI service, which is conceptually patterned after DNS (the Internet service that translates URLs into TCP addresses). UDDI uses a private agreement profile of SOAP (i.e. UDDI doesn't use the SOAP serialization format because it's not well suited to passing complete XML documents (it's aimed at RPC style interactions). The main idea is that businesses use the SOAP APIs to register themselves with UDDI, and other businesses search UDDI when they want to discover a trading partner, for example someone from whom they wish to procure sheet metal, bolts, or transistors. The information in UDDI is categorized according to industry type and geographical location, allowing UDDI consumers to search through lists of potentially matching businesses to find the specific one they want to contact. Once a specific business is chosen, another call to UDDI is made to obtain the specific contact information for that business. The contact information includes a pointer to the target business's WSDL or other XML schema file describing the web service that the target business publishes. 14. How to generate proxy class other than .net app and wsdl tool?To access an XML Web service from a client application, you first add a Web reference, which is a reference to an XML Web service. When you create a Web reference, Visual Studio creates an XML Web service proxy class automatically and adds it to your project. This proxy class exposes the methods of the XML Web service and handles the marshalling of appropriate arguments back and forth between the XML Web service and your application. Visual Studio uses the Web Services Description Language (WSDL) to create the proxy.To generate an XML Web service proxy class: • From a command prompt, use Wsdl.exe to create a proxy class, specifying (at a minimum) the URL to an XML Web service or a service description, or the path to a saved service description.Wsdl /language:language /protocol:protocol /namespace:myNameSpace /out:filename/username:username /password:password /domain:domain 15. What is a proxy in web service? How do I use a proxy server when invoking a Web service? 16. asynchronous web service means? 17. What are the events fired when web service called? 18. How will do transaction in Web Services? 19. How does SOAP transport happen and what is the role of HTTP in it? How you can access a webservice using soap? 20. What are the different formatters can be used in both? Why?.. binary/soap Some example Questions :
1. Explain the differences between Server-side and Client-side code?Server side code basically gets executed on the server (for example on a webserver) per request/call basis, while client side code gets executed and rendered on the client side (for example web browser as a platform) per response basis.
2. What type of code (server or client) is found in a Code-Behind class?In the Code-behind class the server side code resides, and it generates the responses to the client appropriately while it gets called or requested.
3. What does the "EnableViewState" property do? Why would I want it on or off?EnableViewState stores the current state of the page and the objects in it like text boxes, buttons, tables etc. So this helps not losing the state between the round trips between client and server. But this is a very expensive on browser. It delays rendering on the browser, so you should enable it only for the important fields/objects.
4. What is the difference between Server.Transfer and Response.Redirect? Why would I choose one over the other?Server.Transfer transfers the currnet context of the page to the next page and also avoids double roundtrips. Where as Response.Redirect could only pass querystring and also requires roundtrip.
5. How does VB.NET/C# achieve polymorphism?Polymorphism is achieved through virtual, overloaded, overridden methods in C# and VB.NET.
6. Whats an assemblyAn assembly is the primary building block of .NET. It's a reusable, self-describing,versionable deployment unit for types and resources. They are self-describing so to allowthe .NET runtime to fully understand the application and enforce dependency and versioning rules.
7. What is other name for shared assembly?Global Assembly
8. How do you create and use shared assemblies?using GACUtil.exe
9. How do you use thread in your .NET application?Derive your class from Thread Class
10. what are the main differences between Web Server controls and HTML Server controls?HTML Server controls are the nothing but some html tags with runat=server attribute in that tag. Web Server controls have richer event handling. HTML Server Controls need to be nested within a form tag. and so on.
11. Differences between ref and out parameters?out parameter need not be initialized, where as ref parameter needs to be. This clarifies that ref is both I/O parameter and out is only Output parameter as name suggests
12. When on the internet would you look for web services?I guess the question is where on the Internet would you look for web services. Go to UDDI Server and find.
13. Does .NET supports Pessimistic record locking or Optimistic record locking or both?both.
14. What is Catch API?I am not aware of any Catch API. If it is Cache then look for Cache class and if it is exception handling (try catch throw block) look for it.
15. which method do you use to redirect the user to another page without performing a round trip to the client?Server.Transfer
16. What base class do all web forms inherit from?System.web.UI.Page class. But for UserControl its System.Web.UI.UserControl
17. what method do you use to explicitly kill a users session?Session.Abandon
18. Which .NET class is used to validate an XML document?XMLValidatingReader.
19. What is AutoPostBackUse this property to specify whether the state of the control is posted back to the server when clicked, changes, list.
20. What is reflectionThe process of obtaining information about assemblies and the types defined within them, and creating, invoking, and accessing type instances at run time.0 comments Links to this post What are Lambda Expressions? With Lambda expressions you can treat code as data. In C# 1.0 / 2.0, it is common to pass strings, integers, reference types, and so on to methods so that the methods can act on those values.
Anonymous methods and lambda expressions extend the range of the values to include code blocks. This concept is common in functional programming.Explain the delegates in C#. Delegates in C# are objects which points towards a function which matches its signature. Delegates are reference type used to encapsulate a method with a specific signature. Delegates are similar to function pointers in C++; however, delegates are type-safe and secure.Here are some features of delegates: • A delegate represents a class. • A delegate is type-safe. • We can use delegates both for static and instance methods • We can combine multiple delegates into a single delegate. • Delegates are often used in event-based programming, such as publish/subscribe. • We can use delegates in asynchronous-style programming. • We can define delegates inside or outside of classes. Syntax of using delegates
//Declaring delegate delegate void SampleDelegate(string message);
// declare method with same signature:static void SampleDelegateMethod(string message) { Console.WriteLine(message); }
// create delegate object SampleDelegate d1 = SampleDelegateMethod;
// Invoke method with delegated1("my program"); Posted by Gurjinder Singh Brar 1 comments Labels: class, Delegates What is the purpose of connection pooling in ADO.NET? Connection pooling enables an application to use a connection from a pool of connections that do not need to be re-established for each use. Once a connection has been created and placed in a connection pool, an application can reuse that connection without performing the complete connection creation process.
By default, the connection pool is created when the first connection with a unique connection string connects to the database. The pool is populated with connections up to the minimum pool size. Additional connections can be added until the pool reaches the maximum pool size.
When a user request a connection, it is returned from the pool rather than establishing new connection and, when a user releases a connection, it is returned to the pool rather than being released. But be sure than your connections use the same connection string each time. Here is the Syntax
conn.ConnectionString = "integrated Security=SSPI; SERVER=192.168.0.123; DATABASE=MY_DB; Min Pool Size=4;Max Pool Size=40;Connect Timeout=14;";Posted by Gurjinder Singh Brar 0 comments Labels: Connection pooling, connection string What is the difference between classes and structs in Microsoft.Net? • A struct is a value type, while a class is a reference type. • When we instantiate a class, memory will be allocated on the heap. When struct gets initiated, it gets memory on the stack. • Classes can have explicit parameter less constructors. But structs cannot have this. • Classes support inheritance. But there is no inheritance for structs. A struct cannot inherit from another struct or class, and it cannot be the base of a class. Like classes, structures can implement interfaces. • We can assign null variable to class. But we cannot assign null to a struct variable, since structs are value type. • We can declare a destructor in class but can not in struct.Posted by Gurjinder Singh Brar 3 comments Labels: class, constructor, destructor, interface, memory, struct What is a Strong Name in Microsoft.Net? In Microsoft.Net a strong name consists of the assembly's identity. The strong name guarantees the integrity of the assembly. Strong Name includes the name of the .net assembly, version number, culture identity, and a public key token. It is generated from an assembly file using the corresponding private key.Steps to create strong named assembly:
To create a strong named assembly you need to have a key pair (public key and a private key) file. Use sn -k KeyFile.snkOpen the dot net project to be complied as a strong named assembly. Open AssembyInfo.cs/ AssembyInfo.vb file. Add the following lines to AssemblyInfo file.[Assembly: AssemblyVersion("1.0.*")][assembly: AssemblyDelaySign(false)][assembly: AssemblyKeyFile("..\\..\\KeyFile.snk")]Compile the application, we have created a strong named assembly.Posted by Gurjinder Singh Brar 0 comments Labels: .net assembly, Microsoft.Net, private key, public key, strong named assembly What is the use of XSLT? XSLT stands for Extensible Stylesheet Language Transformations. This language used in XSL style sheets to transform XML documents into other XML documents.
XSLT is based on template rules which specify how XML documents should be processed. An XSLT processor reads both an XML document and an XSLT style sheet. Based on the instructions the processor finds in the XSLT style sheet, it produce a new XML document. With XSLT we can also produce HTML or XHTML from XML document. With XSLT we can add/remove elements and attributes, rearrange and sort elements, hide and display elements from the output file. Converting XML to HTML for display is probably the most common application of XSLT today.Posted by Gurjinder Singh Brar 1 comments Labels: Extensible Stylesheet Language Transformations, XML, XML documents, XSL style sheets, XSLT Explain ACID properties of the database? All Database systems which include transaction support implement ACID properties to ensure the integrity of the database. ACID stands for Atomicity, Consistency, Isolation and Durability• Atomicity: Each transaction is said to be “atomic.” If one part of the transaction fails, the entire transaction fails. Modifications on the data in the database either fail or succeed. • Consistency: This property ensures that only valid data will be written to the database. If, for some reason, a transaction is executed that violates the database’s consistency rules, the entire transaction will be rolled back and the database will be restored to a state consistent with those rules. • Isolation: It requires that multiple transactions occurring at the same time not impact each other’s execution. • Durability: It ensures that any transaction committed to the database will not be lost. Posted by Gurjinder Singh Brar 0 comments Labels: ACID properties, Atomicity, Consistency, Database, Durability, Isolation, transaction What is the basic functionality of Garbage Collector in Microsft.Net? The Common Language Runtime (CLR) requires that you create objects in the managed heap, but you do not have to bother with cleaning up the memory once the object goes out of the scope or is no longer needed. The Microsoft .NET Framework Garbage Collector provides memory management capabilities for managed resources. The Garbage Collector frees objects that are not referenced and reclaims their memory. You should set your references to Nothing(null) as soon as you are done with them to ensure your objects are eligible for collection as soon as possible.Here are the list of some tasks performed by the Garbage collector:• Garbage collector reserves a piece of memory as the application starts for the managed heap. • Garbage collector controls the managed heap memory currently used and available to an application. • Garbage collector allocates memory for new objects within the application. • The Garbage Collector attempts to reclaim the memory of objects that are not referenced. Posted by Gurjinder Singh Brar 0 comments Labels: Garbage collector, managed resources, memory management, Microsoft .NET Framework What is a static class? We can declare a static class. We use static class when there is no data or behavior in the class that depends on object identity. A static class can have only static members. We can not create instances of a static class using the new keyword. .NET Framework common language runtime (CLR) loads Static classes automatically when the program or namespace containing the class is loaded.
Here are some more features of static class• Static classes only contain static members. • Static classes can not be instantiated. They cannot contain Instance Constructors • Static classes are sealed. Posted by Gurjinder Singh Brar 0 comments Labels: CLR, common language runtime, Static classes, static members What is static member of class? A static member belongs to the class rather than to the instances of the class. In C# data fields, member functions, properties and events can be declared static. When any instances of the class are created, they cannot be used to access the static member.To access a static class member, use the name of the class instead of an instance variableStatic methods and Static properties can only access static fields and static events.
Like: int i = Car.GetWheels;Here Car is class name and GetWheels is static property.
Static members are often used to represent data or calculations that do not change in response to object state.Posted by Gurjinder Singh Brar 0 comments Labels: static events, static members, static property What is the purpose of Server.MapPath method in Asp.Net? In Asp.Net Server.MapPath method maps the specified relative or virtual path to the corresponding physical path on the server. Server.MapPath takes a path as a parameter and returns the physical location on the hard drive. Syntax
Suppose your Text files are located at D:\project\MyProject\Files\TextFiles
If the root project directory is MyProject and the aspx file is located at root then to get the same path use code
//Physical path of TextFilesstring TextFilePath=Server.MapPath("Files/TextFiles");Posted by Gurjinder Singh Brar 0 comments Labels: physical path, Server.MapPath, virtual path What is the use of indexes and what are the types of indexes available in SQL Server? Indexes are used to find data quickly when a query is processed in any relational database. Indexes improve performance by 10 to 500 times. Index can improve the performance in following operations:• Find the records matching with WHERE clauseUPDATE Books SET Availability = 1 WHERE SubjectId =12 DELETE FROM Books WHERE Price <10SELECT * FROM Books WHERE Price BETWEEN 50 AND 80• Sorting the result with ORDER BYSELECT * FROM Books ORDER BY Price DESC• Grouping records and aggregate valuesSELECT Count(*) as Units, Price FROM Books GROUP BY PriceThere are two types of indexes available in SQL Server: clustered and non-clusteredClustered index Clustered index physically reorders the records of a table. Therefore a table can have only one clustered index. Usually a clustered index will be created on the primary key of a table. Non – Clustered IndexNon – Clustered index are stored in the order of the index key values, but the information in the table is stored in a different order. Means logical sorting of data not Physical. In SQl Server 2005 a table can have 249 non-clustered indexes.Composite IndexesA composite index is an index on two or more columns. Both clustered and non-clustered indexes can be composite indexes. If you have composite index on Price and BookName then take can take advantage of it like this:SELECT BookName, Price FROM Products ORDER BY UnitPrice BookName, Price DESC Posted by Gurjinder Singh Brar 0 comments Labels: Clustered index, Composite Indexes, Indexes, Non – Clustered index, relational database What is the difference between abstract class and interface? We use abstract class and interface where two or more entities do same type of work but in different ways. Means the way of functioning is not clear while defining abstract class or interface. When functionality of each task is not clear then we define interface. If functionality of some task is clear to us but there exist some functions whose functionality differs object by object then we declare abstract class.We can not make instance of Abstract Class as well as Interface. They only allow other classes to inherit from them. And abstract functions must be overridden by the implemented classes. Here are some differences in abstract class and interface.• An interface cannot provide code of any method or property, just the signature. we don’t need to put abstract and public keyword. All the methods and properties defined in Interface are by default public and abstract. An abstract class can provide complete code of methods but there must exist a method or property without body.• A class can implement several interfaces but can inherit only one abstract class. Means multiple inheritance is possible in .Net through Interfaces. • If we add a new method to an Interface then we have to define implementation for the new method in every implemented class. But If we add a new method to an abstract class then we can provide default implementation and therefore all the existing code might work properly. Posted by Gurjinder Singh Brar 0 comments Labels: Abstract Class, abstract functions, interface, multiple inheritance What is the use of Master Pages in Asp.Net? A master page in ASP.Net provides shared HTML, controls, and code that can be used as a template for all of the pages of a website.Every master page has asp:contentplaceholder control that will be filled by the content of the pages that use this master page. You can create a master page that has header and footer i.e. a logo, an image, left navigation bar etc and share this content on multiple pages. You need not to put these things on every aspx page. Posted by Gurjinder Singh Brar 0 comments Labels: ASP.NET, aspx page, master page What is the difference between .Net Remoting and Asp.Net Web Services? • ASP.NET Web Services Can be accessed only over HTTP but .Net Remoting Can be accessed over various protocols like TCP, HTTP, SMTP etc. • Web Services are based on stateless service architecture but .Net Remoting support for both stateful and stateless environment. • Web Services support heterogeneous environments means interoperability across platforms but .Net remoting requires .Net on both server and client end. • .NET Remoting provides the fast communication than Web Services when we use the TCP channel and the binary formatter. • Web services support only the objects that can be serialized but .NET Remoting can provide support to all objects that inherit MarshalByRefObject. • Web Services are reliable than .Net remoting because Web services are always hosted in IIS. • Web Services are ease to create and deploy but .Net remoting is bit complex to program. Posted by Gurjinder Singh Brar 0 comments Labels: .Net Remoting, ASP.NET, binary formatter, Web Services What would be the common layers in an n- tier architecture based web application? Common layers in an n- tier architecture • Presentation GUI: Look & Feel ,Html, aspx file, JavaScript, window forms etc. • Controller- Work flow layer: aspx.cs file, means event handlers and Data binding with controls etc. • Business Logic: where we implement business rules like add book, search library etc. • Data Access: SQLHelper.cs like create connection, get DataSet, Execute Query etc. • Physical Data: tables, views, stored procedures, indexes etc. Posted by Gurjinder Singh Brar 0 comments Labels: Common layers, n- tier architecture What are the different state management techniques used in asp.net for web applications? In ASP.Net the state can be maintained in following waysServer-side state managementApplication objectsSession VariablesDatabaseClient-side state managementCookiesHidden input fieldsQuery StringViewState