1. what is present In httpd.conf file
The httpd.conf file is the main configuration file for the Apache web server.
There are various setting that can be made like
ServerType,
Timeout 300,
MaxClients
2. What is the web server used in your company?
IHS
3. Thread dump n heap dump-commands and Differences?
Thread dump:
A thread represents a work item or task, such as a servlet request. Java processes are usually multi-threaded.
This means there can be many tasks occurring simultaneously (that is, multi-threading) within one JVM (Java Virtual Machine) process.
Therefore, understanding what is occurring within a JVM process means obtaining information about all the different threads that are defined within the process.
This thread information can be obtained with system thread dumps and Java thread dumps. A thread dump contains a set of statements, which help the system administrator to easily identify the problem in the program.
Heap dump:
Heap dump is a feature of IBM JVM that prints a record of all the objects in the java heap to a text file. The size and address of each objects are recorded, so that this information helps to know which objects are taking large amount of memory.
So we can know which object is resulting for memory leak.
By default , websphere application server generates a heap dump in profiles home Directory when ever an outOfMemoryException is thrown.
To disable this feature set the environment variable
“IBM_HEAPDUMP_OUTOFMEMORY=false”
To generate heap dump manually
IBM_HEAPDUMP=”true”
Heap dump command:
1.first get the object name
2.use generateHeapDump command.
<wsadmin> set objectName [$AdminControl queryNames WebSphere:type=JVM,process=<servername>,node=<nodename>,*]
Invoking the generateHeapDump operation on JVM MBean:
<wsadmin> $AdminControl invoke $objectName generateHeapDump
4. What is Connection leak? How to rectify.
A connection which is opened is not closed properly even after the specific purpose is obtained. So that the connection still remains active, even though it is not serving any request.
This will cause for the new connections to wait, till the existing connection is timed out.If the new connection is waited for too long it will throw ConnectionWaitTimeoutException.
To enable the connection leak diagnostics, set the log detail level to “ConnLeakLogic=finest”. And enable the diagnostic tracing.
So that when ever connectionWaitTimeoutException occurs and is obtained in the stack trace, so that it can be diagnosed through the logs.
11. What are all the different roles in was?
Administrator[monitor +Configurator]
Configurator[monitor+change configuration]
Operator[monitor + bounce]
Monitor[only navigation and monitor]
19. If files are full then what command will use in linux?
[to improve the disk space]
44. What is a throughput ?
A generict term.
The amount of work that a computer/resource can do in a given period of time
A measure of effectiveness, productivity andperformance.
44. What is topology?
Topology: the way in which constituent parts are arranged and inter related.
Logical topology: logical topology is some what related to protocols like How data moved, how signals are passed.
Physical topology:
The physical layout of a network how the wires are connected.
[like how the systems are connected in LAN LIKE star topology, bus topology, ring topology.
46. Tell me about your environment and your roles and responsibilities
47. what are all your daily activities????
48. What are the different stages of your environment in your organization???
49. With out opening the box how can u know the status of webserver?
Procedure:- servername is fish port no 7700
$telnet fish 7700
trying to connect 172.20.100.220
connected to zo5.jenks.oas.silvenet
means that the server is up and running
if u get unable to connect the server is stopped.
50. how can u find out port no’s and in which file they are available?
Vpd.properties file
51. how can we list daily used top 5 commands in Linux ?? Tell me 5 commands which are using daily??
52. what is verbose collection? Have u configured it????
Specifies whether to use verbose debug output for garbage collection. The default is not to enable verbose garbage collection.
Console->servers->application servers->server1->Java process management->Process definition->Java Virtual Machine->
Enable Verbose Garbage Collection
And give initial Heap size and Max Heap size .
53. How to set a class path in WAS?
54. How can you find out particular port in Linux?
Netstat –a will list the currently used ports in the OS.
55. What is Replication Domains?
Replication Domains consists servers or clusters members that have need to share internal data, Replication data.
It is responsible for in memory-replication among the websphere process.
1. Stateful session Bean persistence and fail over
2. Http session persistence and fail over
3. Dynamic cache replication
56. What is a cell-config.xml file?
57. What is the difference between Web Server and Application Servier
Webserver:
A Web server handles the HTTP protocol. When the Web server receives an HTTP request, it responds with an HTTP response, such as sending back an HTML page. To process a request, a Web server may respond with a static HTML page or image, send a redirect, or delegate the dynamic response generation to some other program such as CGI scripts, JSPs (JavaServer Pages), servlets, ASPs (Active Server Pages), server-side JavaScripts, or some other server-side technology. Whatever their purpose, such server-side programs generate a response, most often in HTML, for viewing in a Web browser.
Application Server:
As for the application server, according to our definition, an application server exposes business logic to client applications through various protocols, possibly including HTTP. While a Web server mainly deals with sending HTML for display in a Web browser, an application server provides access to business logic for use by client application programs. The application program can use this logic just as it would call a method on an object
58. When using the WebSphere, Which three updates would force you to restart the test environment?
These are the situation when you need to restart the server in test mode.
1) When you make any changes to the Class file(Bean , DAO etc)
2) Change any properties that were declared in properties file related to the whole application. This is because initially properties file that were declared for the application will be loaded only when the server starts, and the server picks up thos key, values.
3) No need to restart if you make any change for jsp file. But you need to comeout of that particular page or refresh the page , so that it will recompile the modified jsp file and generate new contents, But you need to restart the server when you change the servlet file.
4) If the database connection between the DB server and APpserver fails. Because the connection pool and all will be declared in the properties file.
59. In IBM WSAD, server crashes sometime while running in debug mode .Is there any way to prevent it ???
You need to bump the heap size memory default is 0,0 Enable adminstative console in the wsad in the server settings I believe its configuration tab or environment . And logon to the adminconsole on port 9090 when u start the server in normal modehttp://localhost:9090/admin. Then go to server/ server1/process definition/JVMIncrease the initial heap and maximum heap size in there.. Give atleast (512MB,1.5Gb) And restart the server in debug modeIts should work. It worked for me
you need to increase the memmory allocated to java process in WAS. In WASD deployement description there is a setting for java process memmory allocation. Increase the -Xmx values in it and see if thst works for you.
60. How many ways deployments in ibm websphere.please give me one examples.
Ways of deplyment depends on version of WebSphere Application server you are using.
But 5.X and Above provide following ways
1. Using Admin Console
2. Hot Deployment: [dropping jsp files, with enabled class reloading (not recommanded for production)]
3. Using Jacl Scripts
4. using WSAdmin command
5. Rapid Deployment (feature available at WAS 6).
61. Deployment Descriptors Types
What is Deployment Descriptors? How many types of Deployment Descriptors are available? What are they?
According to war file
1.web.xml
2.ibm-web-bnd.xml
3.ibm-web-ext.xml
This file is web.xml
This is an xml file. It tells to the server about the application.
Each web appication contain one deployment descriptor
Deployment Descriptors is a Configuration File ( In XML).
This specifies the configuration for a EJB/Web Contaniner.
It is a sort of file that will be referred by the container, when a specific request in made to the container.
The specifications made by Deployment Descriptor are;
1. Database Connections to be made
2. Location of EJBs
3. How to implement security &
4. Other important settings.
No comments:
Post a Comment