Middleware Interview Questions & Answers

Question 1. What Is Client/server?

Answer :

Client : The client hardware is the desktop machine that runs client software. It could be a micro or a workstation. The client software formulates data request and passes the request to the network software. This software sends the request to the server, accepts the result from the server and passes the request back to the client software.

Server : A server is the machine that runs data management software that has been designed for server functionality. A server has operating system software, data management software and a  portion of the network software.

Question 2. Define File Server?

Answer :

File Server : File servers manage a work group’s applications and data files, so that they may  be shared by the group. File servers are very I/O oriented. They pull large amounts of data  off their storage subsystems and pass the data over the network. When the data from the file  is requested, a file server transmit all records from the file.

Question 3. What Are The Service Specific Middleware Available?

Answer :

ODBC : Open database connectivity is a windows technology that lets a database client application connect to a external database. To use ODBC, the database vendor must provide an ODBC driver for data access.

HTTP : Hyper Text Transfer Protocol is the underlying protocol used by the  world wide web. HTTP defines how messages are formatted and transmitted and  action web servers and browsers should take in response to various  commands. HTTP only supports transmission of text.

Question 4. Define The Services Provided By Web Server?

Answer :

Web server : A webserver is a computer system that delivers web pages. Every web server has an IP address and possibly a domain name.

for example: an URL This sends a request to the server  whose domain name is niceindia.com. the server fetches the page named index.html and sends back to our browsers.

Question 5. Define Tcp/ip And Ipx/spx?

Answer :

TCP/IP : Transfer control Protocol and Internet Protocol.

Question 6. What Is Remote Procedure Call?

Answer :

Remote Procedure Call (RPC): One of the earliest facilities that was created to help programmers write client/server software is known generically as a Remote Procedure Call mechanism. When implementing a program, the programmer uses procedures to keep the code manageable. Instead of defining a single, large procedure that performs many tasks, the programmer divides the tasks  into sets and uses shorter procedure to handle each set. A client procedure process calls a  function on a remote server and suspends itself until it gets back the result. This process that  issues the calls and waits until it gets the result is called remote procedure call.

Question 7. Where The Error Logs In Appear In Z/os?

Answer :

SDSF (spool Display Search Facility)

Question 8. Explain A Cluster?

Answer :

Cluster is said to be group of queue manager's logically  connected together to balance the load on the remote machine (i.e if it is remote queue managers which processes your  message). And there are two types of grouping on the queue  managers.

1) Full repository

2) Partial repository.

The full repository queue manager knows all other queue  managers in the cluster and whenever a message comes to it,  and if that is unable to process the message, it will find  a queue in other queue manager in the cluster and ask it to  process the message.

Question 9. What Is A Queue?

Answer :

Queue is a data structure which is store the messages.and every queue has own queue manager.queue manager are  maintaining the all queues.different types of queues are  available in web sphere mq in different purpose.but generally 4 types of queues r there 

1. local queue
2. remote queue
3. alias queue
4. model queue.

Question 10. How To Connect Tn In Web Methods?

Answer :

After completing jdbc pool.

Question 11. What Is The Next Step?

Answer :

1. Assuming u already executed all TN Database scripts.
2. Go to JDBC Pools its divided into 3 parts.
3. in second part u configure the pool and give a name to that pool ex: TN Pool.
4. in first part u find TN Pools edit and associate the TNPool with that. save and restart the server. u can access the TN server from TN console or MWS.

Question 12. What Is Ssl? How To Assign That Ssl Certificate To Particular Qm?

Answer :

For Windows System,

 1. Need to create the key repository using " strmqikm ".provide the following parameters in the screen which  is opened by the above command,

Key DataBase Type : CMS

File Name : <>.kdb

Location Of The File : 

<>Qmgrs<>ssl Go to certificate providers website and get the  Certificate, So that the certificate will be installed  in out machine..

• The next step is to export the Installed certificate  into the SSL directory. (<>Qmgrs<>ssl)
• Go to Internet Explorer, Tools / Internet Options /  Content / Certificates, From this screen select the  installed Certificate and export the same to the directory, which is mentioned in the above.
• Once the export is done, double click on the *.kdb file  and try to import the certificate, which was exported in  the step 3.

Question 13. What Is A Heap Dump, Thread Dump?

Answer :

Thread Dump: When we trigger a thread dump on a application  server,all active thread informations will be dumped into  file which is known as thread dump. here, we can get  information about thread like active thread,hung  thread,dead lock,runnable and inactive thread info.  Command : kill -3 PID(Process Id).

Heap Dump: It's snap shot of our JVM  heap memory,so here  we can have all active java objects and their activities  which object doing what and how much memory it is  occupying

Question 14. What Are The Installation Modes In Weblogic?

Answer :

The modes of deployment are: Stage,No-stage and External

STAGE: The Administration Server first copies the deployment unit source files to the staging directories of  target servers specified by the Staging Directory Name  attribute.The target servers then deploy using their local copy

NOSTAGE: The Administration Server does not copy deployment unit files. Instead, all servers deploy using the same physical copy of the deployment files, which must  be directly accessible by the Administration Server and  target servers. With nostage deployments of exploded archive directories,  WebLogic Server automatically detects changes to a  deployment's JSPs or Servlets and refreshes the deployment. 

(This behavior can be disabled if necessary.)

EXTERNAL_Storage: The Administration Server does not copy  deployment files. Instead, the Administrator must ensure  that deployment files are distributed to the correct  staging directory location before deployment (for example,  by manually copying files prior to deployment). 

With external_stage deployments, the Administration Server  requires a copy of the deployment files for validation  purposes. Copies of the deployment files that reside in  target servers' staging directories are not validated  before deployment.