Tools / IBM WebSphere Server Interview questions

IBM WebSphere Application Server (WAS) is a tool based on Java and developed by IBM, to manage and create websites. WAS server is often used to build interactive web-oriented applications that support business functions required for e-commerce, it integrates all the data across different operating systems and applications.

The WAS Deployment Manager (Dmgr) is the main administration process that manages all other application servers in a WAS deployment cell, including node agents and application server processes.

Ripple-start is to restart the WAS cluster with zero downtime to the application. It first stops the JVM and then starts it. By doing ripple-start you ensure only one JVM is down at one time hence no downtime to the applications.

Yes, DMGR being down/unavailable doesn't impact the existing running applications on the server. However, if you need to make any changes or perform deployment through DMGR, then that would be impacted.

The default port for HTTP is 9080 and HTTPS 9443.

Go to profile, bin folder and execute ./versionInfo.sh.

A profile defines the runtime environment. The profile includes all the files that the server processes in the runtime environment and that you can change.

Node is a logical grouping of server processes maintained by WebSphere and that share common configuration and operational control.

Each node has a NodeAgent that works along with the deployment manager to manage administration processes. It acts as a mediator between the node and deployment manager.

A Node Group is a grouping of nodes within a cell that have same capabilities.

A cell is a logical grouping of nodes that enables common administrative activities in a WebSphere Application Server distributed environment. A cell can have one or many clusters. A logical grouping of one or more functionally identical application server processes.

The cluster is a logical grouping of one or more functionally identical application server processes. A cluster provides ease of deployment, scalability, workload balancing, and failover redundancy. A cluster is a collection of servers working together as a single system to ensure that mission-critical applications and resources remain available to clients.

The cluster member is an instance of a WebSphere Application Server within a cluster.

WebSphere's web server plugin component routes requests to WebSphere cluster Web Containers (within Application Server JVMs). If it has communication failures with a particular cluster member, it will mark that member down and start routing all requests to the remaining cluster members until the original is available again.

This ensures high availability of the application to the end user.

Hot deployment involves copying application artifact/file directly to the application directory. However, this process is not recommended for production environment and is only suitable for non-production environment.

Scripts: Application deployment done by developing ant tasks or by developing wsadmin scripts.

DMGR: Application deployment via WebSphere Admin Console, clicking a new application option from the Application Menu, the deployment can be done by DMGR.

• Ensure application is always available from one of the cluster members.
• High-availability if one or more JVM is down.
• No issue if one of the cluster JVM’s physical server is down.
• No or minimum downtime during restart.
• Easy maintenance.
• No need to deploy on multiple JVM instead just select the cluster as target.

Horizontal Cluster, widely used clustering type where you host your applications on multiple JVM servers (physical or VM) using a single cluster.

Vertical Cluster have all JVM servers under cluster on single physical or VM server. A vertical cluster can be SPOF (Single point of failure) when a server goes down.

The vertical cluster has its members on the same node or server whereas the horizontal is across multiple nodes and servers in a cell.

The cluster in the WebSphere is partitioned dynamically in asymmetrical clustering and only one cluster can run at a specific allotted time. A particular task can be allotted to a particular cluster.

Virtual hosts are considered to be the ones that consist of various kinds of URLs like FQDN and IP. These are all present in a single application. The configuration of the same is also done with the WebSphere application server. The application must be included in an URL and this is known as the virtual host. Hence, this application remains associated with its URL in the virtual host.

WebSphere supports most of the available databases, including Oracle, Microsoft SQL Server, Sybase, and DB2.

WebLogic is an application server developed by Oracle Corporation. It is written in Java programming language and is available for different platforms. Its last stable release was in 2020. It helps the users to write business logic code and then deploy the application in an easy way. Several functionalities like access to the database, and messaging features for communication are available with it. It supports a large number of modules as compared to WebSphere. Many resources identify that WebLogic is faster than WebSphere.

WebSphere is also an application server from IBM, built using Java, and is mostly used for web applications. It is available for different operating systems like Linux, Solaris, Windows, etc. Initially, it was released in 1998 and the stable version came to the market in 2016. Supported modules are less in the case of WebSphere.

Connecting pool is a cache of database connections maintained so that connection can be re-used when future requests to the database are required. If all the connections are occupied, a new connection is created and is added to the pool.

The syncNode command forces a configuration synchronization to occur between the node and the deployment manager for the cell in which the node is configured. The node agent server runs a configuration synchronization service that keeps the node configuration synchronized with the master cell configuration.

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.

PMT (profile management tool) is a GUI to create and manage the WebSphere profiles.