What is Weblogic?
WebLogic is a J2EE application server and also an HTTP web server by Oracle, for UNIX, Linux, Microsoft Windows, and other platforms. WebLogic supports Oracle, DB2, Microsoft SQL Server, and other JDBC-compliant databases.
What is the name of default JVM that is made used for WebLogic?
The sun hotspot JDK default is made used for development, JRockit is the one used for production of WebLogic 11g as well as 12c. Operating system is another factor that helps in choosing the certified JDK JVM.
We often see BSU when using weblogic. What is the meaning of BSU?
Oracle bought Weblogic from BEA. BSU Stands for Bea Smart Update. This utility is used to apply the WebLogic Server Patches. In simple terms, it is first letter of name of founders Bill Coleman, Ed Scott and Alfred Chuang.
What is the Basic Components of Weblogic Server?
These are the basic weblogic components
1)Domains
2)Admin Server
3) Managed Server
4) Node Manager
5) Weblogic Server Cluster
Explain the methods for providing user credentials for starting the server?
At the time of the creation of domain, the wizard for setting configuration asks for the details like user name, password etc. from the user who is logging in for the first time as an administrator. If the domain is created in development mode, the configuration wizard saves the encrypted password as well as the username inside an identity file. This file is available for reference during the time of booting so that in the absence of this file, system can prompt the user for the purpose of entering credentials. A new boot – identity file can be created if you want to change the use credentials or else if you are having the requirement of creating domain in the production mode.
What is the Basic Components of Weblogic Server?
These are the basic weblogic components
1)Domains
2)Admin Server
3) Managed Server
4) Node Manager
5) Weblogic Server Cluster
Explain the methods for providing user credentials for starting the server?
At the time of the creation of domain, the wizard for setting configuration asks for the details like user name, password etc. from the user who is logging in for the first time as an administrator. If the domain is created in development mode, the configuration wizard saves the encrypted password as well as the username inside an identity file. This file is available for reference during the time of booting so that in the absence of this file, system can prompt the user for the purpose of entering credentials. A new boot – identity file can be created if you want to change the use credentials or else if you are having the requirement of creating domain in the production mode.
What is the Admin Server?
Admin Server is the central domain configuration interface which is used to create, delete and
configure the resources of a domain like managed server, machine, cluster, data source, work managers etc.
What are the capabilities of WebLogic server?
There are various capabilities associated with WebLogic server and they are
Changes in dynamic configuration.
Production application redeployment.
Rolling upgrades.
How Administration server and Managed servers will interact?
The Administration Server stores the master copy of the domain configuration, including the
configuration for all Managed Servers in the domain. Each Managed Server stores a local copy of the domain configuration file. When a Managed Server starts, it connects to the administration Server to synchronize the configuration. When the configuration is changed, the Administration Server sends the changed configuration to the Managed Servers.
Why node manager is required?
A Node Manager process is not associated with a specific WebLogic domain but with a machine. You can use the same Node Manager process to control server instances in any WebLogic Server domain, as long as the server instances reside on the same machine as the Node Manager process. Node Manager must run on each computer that hosts WebLogic Server instances. Whether Administration Server or Managed Server that you want to control with Node Manager.
How do stubs function inside WebLogic server cluster at the time of failure?
Stubs perform the process of removing the failed instance from the list whenever there is a failure. The stub usually makes use of DNS for finding the running server and also for obtaining the list of the instances that are currently available with the application. List of the instances available with the server inside cluster gets periodically refreshment and allows in acquiring advantages associated with new servers. The advantages are gained as the server gets added to the cluster.
How many types of weblogic installation?
There are 3 types of weblogic installation.
(a) Graphical Mode (interactive GUI based)
(b) Console Mode (interactive Text Based)
(c) Silent Mode (Non Interactive method using .xml properties file)
How clients handle the DNS – requests to the failed servers?
Bandwidth gets wasted in the case of continues DNS requests to that of unavailable machine at the time of server failure. This problem usually occurs during the time of startup associated with the application that of client side. The servers that are unavailable are removed by searching DNS entries provided by WebLogic server. This removal prevents the clients from accessing failed servers. A third party load – balancers are made used for avoiding the unnecessary DNS requests. Some of the third party load – balancers are BigIP, resonate, local director and Alteon. The main function of these third party loads – balancers is to mask multiple addresses of DNS in to a single one.
What is the difference between the Sun JVM and BEA JRockit JVM?
The most well know JVM is the implementation from Sun. The Sun JVM is called HotSpot. The Sun JVM is shipped in the Java Developer’s Kit (JDK) and Java Runtime Environment (JRE) from Sun.
The BEA JRockit JVM from BEA systems is optimized for reliability and performance for server side applications. To achieve this, BEA JRockit JVM uses technologies such as code generation, hot spot detection, code optimization, advanced garbage collection algorithms and tight operating system integration.
Explain the functioning of Stub?
Stub is usually expected by the people who connect to the WebLogic server cluster. The stub has the list that consists of the available instances of server that perform host implementations associated with object. The stub also has the functionality of balancing the load by distributing load amongst the host servers.
What are the steps for the creation of Pooling within Tomcat server?
The first step involved in this process of creating pooling is to download 3 jar files which are the commons-dbcp-1.2 jar, commons-pool-1.3.jar and commons-collections-3.1 jar.
The next step is to make an entry inside server.xml of tomcat factory.
What is the default port of Weblogic admin server?
By default weblogic admin server configured on port 7001 and SSL is on 7002.
How can Server Hang be solved?
Java WebLogic.Admin PING needs to be checked for finding whether you get a normal and positive response. You can find out the root cause for hanging from this file. You just need to rectify the errors that are identified from this file.
What is the advantage of clustering?
WebLogic clustering offers three important benefits:
1. Scalability:
The capacity of an application deployed on a WebLogic Server cluster can be increased dynamically to meet demand. You can add server instances to a cluster without interruption of service — the application continues to run without impact to clients and end users.
2. Load balancing:
The ability to distribute requests across all members of the cluster, according tothe workload on each server.
3. High availability:
A mix of features that ensure applications and services are available even if aserver or machine fails. Clients can continue to work with little or no disruption ina highly available environment. WebLogic achieves high availability using a combination of features: replication, failover, and migratable services.
