Websphere Admin Interview Questions & Answers
1. What is WebSphere?
Answer: WebSphere is a set of Java-based tools from IBM that allows customers to create and manage sophisticated business Web sites. The central WebSphere tool is the WebSphere Application Server (WAS), an application server that a customer can use to connect Web site users with Java applications or servlets.
2. Define Default messaging provider?
Answer: The default messaging provider uses the service integration bus for transport. The default message provider provides point-to-point functions, as well as publish and subscribe functions. Within this provider, you define JMS connection factories and destinations that correspond to service integration bus destinations.
3. How to deploy an application in WebSphere?
There are three possible ways to deploy:
Hot deployment: copy the application file into the application directory. This is good for the non-production environment and not recommended for production.
DMGR: You can deploy an application through DMGR by going to Applications >> New application
Scripts: You can develop wsadmin scripts or ant tasks for application deployment.
4. Explain About The Network Deployment Feature Present In Was?
Managing singletons will be a thing of the past and it also provides hot recovery of singletons which makes you forget about your GC collected singletons. Transaction logs can be stored on a shared file system. For clustering run, time operations deployment manager`s role was eliminated. J2EE failover support and cell configuration support is also present.
5. Is The Naming Of Connection Factory Independent Of The Name Specified By Jms Client?
Answer: Yes, the naming of the connection factory is independent of the name specified by the JMS client. This is made possible by WAS with its resource references. It isolates the application from object names. This feature is important because it gives us the flexibility to change the administered object without changing the JMS client code.
6. What Is The Trace?
Answer: A trace is an informational record that is intended for service engineers or developers to use. As such, a trace record might be considerably more complex, verbose and detailed than a message entry.
7. What About Plug-in?
Answer: plug-in is one of the modules it is the interface between the application server and web server, the plug-in process receives the request from the client first. If the request is for dynamic content, the plug-in diverts the request to the WebSphere application server. If the request is for static content, the plug-in forwards it to the Http server.
8. What Is The Difference Between Web Server And Application Server?
Answer: Web server serves pages for viewing in a web browser, the application server provides exposes business logic for client applications through various protocols
Web server exclusively handles Http requests. application server serves bussiness logic to application programs through any number of protocols.
Webserver delegation model is fairly simple when the request comes into the web server,it simply passes the request to the program best able to handle it(Server-side program). It may not support transactions and database connection pooling.
The application server is more capable of dynamic behavior than the webserver. We can also configure the application server to work as a webserver. Simply apply! ation server is a superset of the webserver.
9. Why Use The Boostrap Port Number?
Answer: client applications use the bootstrap port to access web spheres built-in object request broker (orb) to use enterprise java beans in applications installed on the application server. The java naming and directory interface service provider URL used by the client application needs to reference the bootstrap port to obtain an initial context for looking up EJB’s it wants to use. (For communicate two servers)
10. Application Installed But Not Working. What Are Troubleshooting Steps?
Answer: see jvm & application is up, check the plugin-cfg.xml file for the root context used by the web application if it does not exist generate plugin and restart the webserver.
11. What Are The Different Modes Of Archival? Explain Each Mode In Two Lines Each?
Answer: Rotate, rotate the log file when the maximum size is reached. The appliance creates a copy of the file and starts a new file. The appliance retains the archived copies up to the specified number of rotations. After reaching the maximum number of rotations and the log file reaches its maximum size, the appliance deletes the oldest file and copies the current file.
Upload, upload the log file when the maximum size is reached. The appliance uploads the file using the specified upload method.
12. What Is Cryptography? Why Do We Need It?
Answer: Cryptography is to protect private communication in the public world. For example, two entities wanting to communicate – Ajitab and Mulu – are shouting their messages in a room full of people. Everyone can hear what they are saying. The goal of cryptography is to protect this communication so that only Ajitab and Mulu can understand the content of the messages.
13. What Are The Weakness Of Symmetric Key Cryptography And What Is The Strength Of The Asymmetric Key Cryptography?
Symmetric key cryptography-
The biggest obstacle in successfully deploying a symmetric-key algorithm is the necessity for a proper exchange of private keys. This transaction must be completed in a secure manner. If the face-to-face meeting, which proves quite impractical in many circumstances when taking distance and time into account, cannot be possible to exchange private keys. If one assumes that security is a risk, to begin with, due to the desire for a secret exchange of data in the first place, the exchange of keys becomes further complicated.
Another problem concerns the compromise of a private key. In symmetric-key cryptography, every participant has an identical private key. As the number of participants in a transaction increases, both the risk of compromise and the consequences of such a compromise increase dramatically. Each additional user adds another potential point of weakness that an attacker could take advantage of. If such an attacker succeeds in gaining control of just one of the private keys in this world, every user, whether there are hundreds of users or only a few, is completely compromised.
Both Symmetric and Asymmetric-key cryptography also has vulnerabilities to attacks such as the man in the middle attack. In this situation, a malicious third party intercepts a public key on its way to one of the parties involved. The third-party can then instead pass along his or her own public key with a message claiming to be from the original sender. An attacker can use this process at every step of an exchange in order to successfully impersonate each member of the conversation without any other parties having knowledge of this deception.
Asymmetric cryptography –More secure
Asymmetric keys must be many times longer than keys in symmetric-cryptography in order to boost security. While generating longer keys in other algorithms will usually prevent a brute force attack from succeeding in any meaningful length of time, these computations become more computationally intensive. These longer keys can still vary in effectiveness depending on the computing power available to an attacker.
14. Explain the Datapower File Structure?
Answer: File system structure in DataPower is one of the main components that we need to look out for while working on day to day activities. Below image shows the directory structure in DataPower.
Following are details of all the Folders present and their description.
audit: This directory contains the audit logs. Each appliance contains only one audit: directory. This directory cannot be the destination of a copy. This directory is available from the CLI in only the default domain.
cert: This encrypted directory contains private key and certificate files that services use in the domain. You can add, delete, and list files in this directory but you cannot view or modify these files. Each application domain contains one cert: directory. This directory is not shared across domains.
checkpoints: This directory contains the configuration checkpoint files for the appliance. Each application domain contains one checkpoints: directory. This directory is not shared across domains. During an upgrade, the operation deletes the contents of this directory.
config: This directory contains the configuration files for the appliance. Each application domain contains one config: directory. This directory is not shared across domains.
desert: This encrypted directory contains files that the appliance itself uses. This directory is available from the CLI in only the default domain.
export: This directory contains the export packages. Each application domain contains one export: directory. This directory is not shared across domains.
image: This directory contains the firmware images (primary and secondary) for the appliance. This directory is where firmware images are stored typically during an upload or fetch operation. Each appliance contains only one image: directory. This directory is available in only the default domain. During an upgrade, the operation deletes the contents of this directory.
internalconfig: This hidden directory contains configuration-like artifacts for the appliance. This directory is where predefined deployment artifacts like pattern exemplars are stored. You cannot access this directory with any interface.
ISA cert: This directory contains a shared certificate and key files. When a shared file is changed, all reverse proxies must be restarted.
isamconfig: This directory contains the following files.
The Access Manager Reverse Proxy configuration files. There is one configuration file per reverse proxy. The files are named in the isamconfig:///webseald-name.conf format.
The Access Manager Reverse Proxy routing files. There is one routing file per reverse proxy. The files are named in the isamconfig:///routing-name format.
isamwebroot: This directory contains files for each Access Manager Reverse Proxy. When a file in this directory is changed, only the reverse proxy that is modified must be restarted.
local: This directory contains miscellaneous files that are used by the services within the domain, such as XSL, XSD, and WSDL files. Each application domain contains one local: directory. This directory can be made visible to other domains. When viewed from other domains, the directory name changes from local: to the name of the application domain.
log store: This directory contains log files that are stored for future reference. Typically, the logging targets use the log temp: directory for active logs. You can move log files to the log store: directory. Each application domain contains one log store: directory. This directory is not shared across domains.
log temp: This directory is the default location of log files, such as the appliance-wide default log. This directory can hold 13 MB. This directory cannot be the destination of a copy. Each application domain contains one log temp: directory. This directory is not shared across domains.
policy framework: This directory contains unattached policies that are submitted to the appliance through the REST management interface. Do not modify files in this directory. To modify an unattached policy, DELETE and POST the policy through the REST management interface. This process ensures that the policy is recompiled. This directory is not shared across domains.
puberty: This encrypted directory contains the security certificates that are used commonly by web browsers. These certificates are used to establish security credentials. Each appliance contains only one pub cert: directory. This directory is not shared across domains. However, you must be in the default domain to upload or fetch files.
shared cert: This encrypted directory contains security certificates that are shared. Each appliance contains only one shared cert: directory. This directory is not shared across domains. However, you must be in the default domain to upload or fetch files.
store: This directory contains example stylesheets, default stylesheets, and schemas that the appliance itself uses. Do not modify files in this directory. Each appliance contains only one store: directory. Although this directory is visible to all domains, you can change the contents of this directory from only the default domain.
task templates: This directory contains the XSL files that define the display of specialized GUI screens. Each appliance contains only one task templates: directory. This directory is available in only the default domain.
temporary: This directory is used as a temporary disk space by processing rules. Each application domain contains one temporary: directory. This directory is not shared across domains. During an upgrade, the operation deletes the contents of this directory.
15. Explain The Attribute Channel In Websphere Mq.?
Answer: A channel is a connection that is to establish a link between a sending channel and receiving channel. A channel has a sender channel at the local queue manager and receiver channel at the remote queue manager. These two channels consist of the same name and together make one channel.
The CHANNEL attribute is used with WebSphere MQ applications to specify the channels for receiving and sending messages in a file that defines sender and receiver channels.
16. Explain The Architecture Of Web Sphere.?
Answer: WebSphere architecture consists of one or more computer systems which are called nodes. Nodes are available within the WebSphere cell. A WebSphere cell can have one node. On this node all the needed software installed. If a WebSphere cell contains more than one node, then all the software components are distributed among the nodes. The software components that are installed in one node can share in the distributed environment. This distribution enables for scalability, reliability.
The following are the components:
- A web server which provides the services of HTTP
- A database server for data persistence
- WebSphere Application Server (WAS)
17. What Is Extended Deployment In Web Sphere?
Answer: WebSphere Extended Deployment is a new product for the IBM WebSphere software. WED extends the WebSphere software platform. The new features/notions include dynamic operations, high-performance computing, and extended management.
18. I Installed A New Application, What Do I Need To Do Before I Can Access It From The Web Server Url?
Answer: When you install a new application or update an application, your web server needs to be aware of the changes. Which means you need to update the webserver plug-in configuration file. So after a successful installation of an application with mapping to web server, you need to regenerate the plug-in configuration file and propagate it to a web server.
19. Are There Any Differences Between Weblogic And Websphere?
Answer: Websphere tends to focus more on integration, connectivity and web services. it has a rich implementation of J2EE, better performance, more extensive integration, and transaction management. In terms of the transaction, WebLogic is having the default transaction attribute as ’supports’, but WebSphere does not have any default transaction attribute.
Websphere is from IBM and Weblogic is from BEA.
20. What is local rendering and remote rendering?
Answer: The web content management portlets can be rendered local or remotely. A local rendering portlet displays content on the same portal as the instance where the web content manager is installed. A remote rendering portlet displays Web content on a different portal server than the instance where Web Content Manager is installed.
21. What are Authoring and Presentation Templates?
Answer: Authoring Template- This template is defined using authoring portlet, where we define the access information, form properties, and default content. It does not contain any information for presentation and The elements in this form are linked to the presentation template.
Presentation Template- This allows to change the look of a page without having to update what is being displayed on a page. It will allow defining Page style, Page layout and map element to the authoring templates.
22. What is the difference between Application Server and Portal Server?
Answer: Application servers extend the ability of a Web server to handle Web application requests and enable a server to generate a dynamic, customized response to a client request. A portal server extends the application server by providing a portlet container that can run portlets and create portal a website that provides users with a single point of access to Web-based resources by aggregating those resources in one place.
23. What is an Application group and why would I want to use it?
Answer: Application groups is a concept that allows you to define user groups within the database user registry with members (users or groups) contained in the LDAP user registry you configured.
The benefit of application groups is that you can create Groups that are only used in WebSphere Portal particularly in scenarios where there is Read-only LDAP or special group set up specific to the portal.
24. What are the different states of the syndication process?
Idle: No syndication is occurring.
Pending: A request has been made to the syndicator, but it has yet to initiate a request to the syndication application.
Queued: The syndicator has sent a request to the syndication application, but syndication is not yet active.
Active: Syndication is occurring between the syndicator and subscriber.
Disabled: Syndication is currently disabled.
25. What is the PortletSession interface?
Answer: User identification across many requests and transient information storage about the user is processed by the PortletSession interface. One PortletSession is created per portlet application per client.
The PortletSession interface provides a way to identify a user across more than one request and to store transient information about that user.
The storing of information is defined in two scopes- APPLICATION_SCOPE and PORTLET_SCOPE.
APPLICATION_SCOPE: All the objects in the session are available to all portlets, servlets, JSPs of the same portlet application, by using APPLICATION_SCOPE.
PORTLET_SCOPE: All the objects in the session are available to the portlet during the requests for the same portlet window. The attributes persisted in the PORTLET_SCOPE are not protected from other web components.
26. What is the purpose of the Release Builder tool in WebSphere Portal?
Answer: Release Builder enables management of release configurations independent of user configurations and used during the staging of follow-on releases of WebSphere portals, configurations, and artifacts need to be moved between systems. (Company)
27. What is an Application group and why would I want to use it?
Answer: Application groups is a concept that allows you to define user groups within the database user registry with members (users or groups) contained in the LDAP user registry you configured. The benefit of application groups is that you can create Groups that are only used in WebSphere Portal particularly in scenarios where there is Read-only LDAP or special group set up specific to the portal.
28. How do you enable temporary and extended trace logging for WebSphere Portal?
Answer: Temporary traces can be set for a temporary period by using the administration portlet Enable Tracing or the IBM WebSphere Application Server administrative console and also using the Enable Tracing portlet in the portal administration page.
To enable extended trace settings for a longer period of time, that is, for more than one session, switch them on in the WebSphere Application Server configuration, save the updates and restart the portal server.
29. What is the difference between Application Server and Portal Server?
Answer: Application servers extend the ability of a Web server to handle Web application requests, and enables a server to generate a dynamic, customized response to a client request. A portal server extends the application server by providing a portlet container that can run portlets and create portal a website that provides users with a single point of access to Web-based resources by aggregating those resources in one place.
30. What is LDAP realm support and why would I want to use it?
Answer: A Realm allows you to group users from one or more LDAP trees of one user registry and expose them as a coherent user population to WebSphere Portal; this is also referred to as horizontal partitioning. Realms allow flexible user management with various configuration options; for example, you can combine principals from one or more corporate LDAP tree. A realm must be mapped to a Virtual Portal to allow the realm’s defined user population to login to the Virtual Portal.
31. what is a Message and what does it contain?
Answer: A message is a string of bytes that is meaningful to the applications that use it. Messages are used to transfer information from one application program to another (or between different parts of the same application). The applications can be running on the same platform, or on different platforms.
WebSphere MQ messages have two parts:
1. The application data. The content and structure of the application data are defined by the application programs that use it.
2. A message descriptor. The message descriptor identifies the message and contains additional control information, such as the type of message and the priority assigned to the message by the sending application. WebSphere MQ defines the format of the message descriptor.
32. Mention the Different Types of MQ Queues?
There are four types of Queues Available in Web sphere MQ
Local queue object: A local queue object identifies a local queue belonging to the queue manager to which the application is connected. All queues are local queues in the sense that each queue belongs to a queue manager and, for that queue manager; the queue is a local queue.
Remote queue object: A remote queue object identifies a queue belonging to another queue manager. This queue must be defined as a local queue to that queue manager. The information you specify when you define a remote queue object allows the local queue manager to find the remote queue manager so that any messages destined for the remote queue go to the correct queue manager.
Alias queue object An alias queue allows applications to access a queue by referring to it indirectly in MQI calls. When an alias queue name is used in an MQI call, the name is resolved to the name of either a local or a remote queue at run time. This allows you to change the queues that applications use without changing the application in any way; you merely change the alias queue definition to reflect the name of the new queue to which the alias resolves. An alias queue is not a queue, but an object that you can use to access another queue.
Model queue object A model queue defines a set of queue attributes that are used as a template for creating a dynamic queue.
33. What is the Different Logging Methods available?
There are two different types available
1. Circular: The circular logging is used for restart recovery. It is the default logging method. Circular is used in Development and Testing Queues. Circular logging keeps all restart Data in a ring of log files. Logging fills the first file in the ring, then moves on to the and so on, until all the files are full. It then goes back to the first file in the ring and starts This continues as long as the product is in use, and has the advantage that you never run out of log files.
2. Linear: Linear logging gives you both restart recovery and media recovery. It is used in Production. Linear logging keeps the log data in a continuous Sequence of files. Space is not reused, so you can always retrieve any record logged from the time that the queue manager was created. As disk space is finite, you might have to think about some form of archiving. It is an administrative task to manage your disk space for the log, reusing Or extending the existing space as necessary.
34. What is the difference between Persistent and Non-Persistent Messages?
Answer: In the Web Sphere MQ, messages can be either persistent or nonpersistent. Persistent messages are logged and can be recovered in the event of a WebSphere MQ failure. Thus, persistent messages are guaranteed to be delivered once and only once. Nonpersistent messages are not logged. Web Sphere still guarantees to deliver them not more than once, but it does not promise to deliver them once.
35. What is Intercommunication?
Answer: In Web Sphere MQ, intercommunication means sending messages from one Queue manager to another. The receiving queue manager could be on the same machine or another; nearby or on the other side of the world. It could be running on the same platform as the local queue manager or could be on any of the platforms supported by Web Sphere MQ. This is called a distributed environment. Web Sphere MQ handles communication in a distributed environment such as this using Distributed Queue Management (DQM).
The local queue manager is sometimes called the source queue manager and the remote queue manager is sometimes called the target queue manager or the partner queue manager.
36. What is Message Channel agent (MCA)?
Answer: A message channel agent (MCA) is a program that controls the sending and receiving of messages. There is one message channel agent at each end of a channel. One MCA takes messages from the transmission queue and puts them on the communication link. The other MCA receives messages and delivers them onto a queue on the remote queue manager.
A message channel agent is called a caller MCA if it initiated the communication; otherwise, it is called a responder MCA.
37. What are Channel initiators and Listeners?
Answer: A channel initiator acts as a trigger monitor for sender channels, because a transmission queue may be defined as a triggered queue. When a message arrives on a transmission queue that satisfies the triggering criteria for that queue, a message is sent to the initiation queue, triggering the channel initiator to start the
appropriate sender channel. You can also start server channels in this way if you specified the connection name of the partner in the channel definition. This means that channels can be started automatically, based upon messages arriving on the appropriate transmission queue.
You need a channel listener program to start receiving (responder) MCAs. Responder MCAs are started in response to a startup request from the caller MCA; the channel listener detects incoming network requests and starts the associated channel.
38. How many no Full Repository Queue Managers are required for creating a cluster. What is the difference between full and partial repositories?
Answer: In each cluster, you must select at least one, preferably two, or possibly more of the queue managers to hold full repositories. A cluster can work quite adequately with only one full repository but using two improves availability. Every cluster has at least one (preferably two) queue managers holding full repositories of information about the queue managers, queues, and channels in a cluster. These repositories also contain requests from the other queue managers in the cluster for updates to the information. The other queue managers each hold a partial repository, containing information about the subset of queues and queue managers with which they need to communicate.
39. What are the different modes in which an application can connect to a Queue manager?
1.Binding mode: In binding mode, also known as server connection, the communication to the queue manager utilizes inter-process communications. One of the key factors that should be kept in mind is that binding mode is available only to programs running on the MQSeries server that hosts the queue manager. A program using binding mode will not run from an MQSeries client machine. Binding mode is a fast and efficient way to interact with MQSeries. Certain Facilities, such as XA transaction co-ordination by the queue manager, are available only in binding mode.
2. Client Connection: Client connection uses a TCP/IP connection to the MQSeries Server and enables communications with the queue manager. Programs using client connections can run on an MQSeries client machine as well as on an MQSeries server machine. Client connections use client channels on the queue manager to communicate with the queue manager. The client connection does not support XA transaction coordination by the queue manager.
40. What are the different types of messaging systems used by JMS?
Answer: JMS applications use either the point-to-point (PTP) or publish/subscribe style of messaging.
Point-to-Point: Point-to-point messaging involves working with queues of messages. The sender sends messages to a specific queue to be consumed normally by a single receiver. In point-to-point communication, a message has at most one recipient. A sending client addresses the message to the queue that holds the messages for the intended (receiving) client.
Publish/Subscribe: In contrast to the point-to-point model of communication, the publish/subscribe model enables the delivery of a message to multiple recipients. A sending client addresses, or publishes, the message to a topic to which multiple clients can be subscribed. There can be multiple publishers, as well as subscribers, to a topic.
41. What are the Hardware requirements for WebSphere MQ client?
Answer: A WebSphere MQ client can run on Windows on any Intel 486 processor-based IBM PC machine or equivalent that can run Windows 98 or Windows NT® 4.0. There must be enough random access memory (RAM) and disk storage for the programming prerequisites (below), the WebSphere MQ client, the access methods, and the application programs.
42. Difference Between Mqsc Commands And Control Commands?
Answer: MQSC Commands: These commands are used to handle the admin related functions for the components that are present in the MQ Series. In general MQSC commands are used for creating and maintaining Message channels, Queue Managers, Clusters, etc…
Control Commands: These commands are used to manage the processes and services that are helpful in the functioning of the MQ Series. In general, these commands are used for Channel listener, Channel Initiator, Trigger monitor, etc…
43. What is the difference between Web Server and Application Server?
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