A WebLogic Server cluster consists of multiple WebLogic Server server instances running simultaneously and working together to provide increased scalability and reliability.
A cluster appears to clients to be a single WebLogic Server instance. The server instances that constitute a cluster can run on the same machine, or be located on different machines. You can increase a cluster's capacity by adding additional server instances to the cluster on an existing machine, or you can add machines to the cluster to host the incremental server instances. Each server instance in a cluster must run the same version of WebLogic Server.
This section describes how to configure clusters. This section includes the following tasks:
To configure general settings for a cluster:
From the Welcome Page, select Targets, then select Middleware.
In the Targets table, select your WebLogic domain. If prompted, enter your user credentials to log in to the WebLogic domain.
In the Target Navigation pane, select the cluster you want to configure.
From the WebLogic Cluster menu, select Administration, then select General Settings.
From the General Settings page you can define the general settings for a cluster, such as:
Name
Default Load Algorithm
Cluster Address
Number of Servers in Cluster Address
Enable Transaction Affinity
For more information about these fields, see Configuration Options.
Optionally, expand Advanced to define advanced settings for this cluster.
Click Save.
To configure JTA for a cluster:
From the Welcome Page, select Targets, then select Middleware.
In the Targets table, select your WebLogic domain. If prompted, enter your user credentials to log in to the WebLogic domain.
In the Target Navigation pane, select the cluster you want to configure.
From the WebLogic Cluster menu, select Administration, then select Java Transaction API (JTA).
From the Java Transaction API (JTA) page you can define the JTA settings for a cluster, such as:
Timeout Seconds
Abandon Timeout Seconds
Before Completion Iteration Limit
Max Transactions
Max Unique Name Statistics
Checkpoint Interval Seconds
Forget Heuristics
Unregister Resource Grace Period
Execute XA Calls in Parallel
Enable Two Phase Commit
Enable Tightly Coupled Transactions
Enable Cluster-Wide Recovery
For more information about these fields, see Configuration Options.
Optionally, expand Advanced to define advanced settings for this cluster.
Click Save.
Clusters use messaging for sharing session, load balancing and failover, JMS, and other information between cluster members. Clusters can use either unicast or multicast messaging. Multicast is a simple broadcast technology that enables multiple applications to subscribe to a given IP address and port number and listen for messages, but requires hardware configuration and support. Unicast does not have these requirements.
To configure messaging for a cluster:
From the Welcome Page, select Targets, then select Middleware.
In the Targets table, select your WebLogic domain. If prompted, enter your user credentials to log in to the WebLogic domain.
In the Target Navigation pane, select the cluster you want to configure.
From the WebLogic Cluster menu, select Administration, then select Messaging.
From the Messaging page, you can define the messaging settings for your cluster, such as:
Messaging Mode
Unicast Broadcast Channel
Multicast Address
Multicast Port
For more information about these fields, see Configuration Options.
Optionally, expand Advanced to define advanced settings for this cluster.
Click Save.
To configure server instances in a cluster:
From the Welcome Page, select Targets, then select Middleware.
In the Targets table, select your WebLogic domain. If prompted, enter your user credentials to log in to the WebLogic domain.
In the Target Navigation pane, select the cluster you want to configure.
From the WebLogic Cluster menu, select Administration, then select Servers.
From the Servers page, you can define settings for server instances in the cluster, such as:
Server Template
Maximum Number of Servers
Server Name Prefix
Enable Calculated Listen Ports
Enable Calculated Machine Associations
Machine Name Match Expression
For more information about these fields, see Configuration Options.
Click Save.
To configure replication for a cluster:
From the Welcome Page, select Targets, then select Middleware.
In the Targets table, select your WebLogic domain. If prompted, enter your user credentials to log in to the WebLogic domain.
In the Target Navigation pane, select the cluster you want to configure.
From the WebLogic Cluster menu, select Administration, then select Replication.
From the Replication page, you can configure how WebLogic Server will replicate HTTP session state across a cluster, including settings such as:
Cross-cluster Replication Type
Remote Cluster Address
Replication Channel
Data Source for Session Persistence
Persist Sessions on Shutdown
Secure Replication Enabled
For more information about these fields, see Configuration Options.
Optionally, expand Advanced to define advanced settings for this cluster.
Click Save.
If a clustered server fails, Node Manager can automatically restart the server instance and its services on another machine. You can specify the machines where Node Manager can restart migratable servers and also the data source used during server migration.
To configure server migration in a cluster:
From the Welcome Page, select Targets, then select Middleware.
In the Targets table, select your WebLogic domain. If prompted, enter your user credentials to log in to the WebLogic domain.
In the Target Navigation pane, select the cluster you want to configure.
From the WebLogic Cluster menu, select Administration, then select Migration.
From the Migration page, you can specify settings related to cluster migration, such:
Candidate Machines for Migratable Servers
Migration Basis
Data Source for Automatic Migration
Auto Migration Table Name
Member Death Detector Enabled
Member Discovery Timeout
Leader Heartbeat Period
Additional Migration Attempts
Pause Time Between Migration Attempts
For more information about these fields, see Configuration Options.
Click Save.
This section describes how to configure and control singleton services.
This section includes the following sections:
To configure general settings for a cluster singleton service:
From the Welcome Page, select Targets, then select Middleware.
In the Targets table, select your WebLogic domain. If prompted, enter your user credentials to log in to the WebLogic domain.
In the Target Navigation pane, select the cluster you want to configure.
From the WebLogic Cluster menu, select Administration, then select Singleton Services.
In the Singleton Services table, select the singleton service you want to configure.
Select Configuration, then select General.
From the General page, you can define settings for the class associations of this singleton service, such as:
Name
Class Name
Additional Migration Attempts
Sleep Time Between Attempts
For more information about these fields, see Configuration Options.
Click Save.
To configure migration for a cluster singleton service:
From the Welcome Page, select Targets, then select Middleware.
In the Targets table, select your WebLogic domain. If prompted, enter your user credentials to log in to the WebLogic domain.
In the Target Navigation pane, select the cluster you want to configure.
From the WebLogic Cluster menu, select Administration, then select Singleton Services.
In the Singleton Services table, select the singleton service you want to configure.
Select Configuration, then select Migration.
From the Migration page, you can define migration settings for this singleton service, such as:
Name
User Preferred Server
Constrained Candidate Servers
For more information about these fields, see Configuration Options.
Click Save.
To create notes for a singleton service:
From the Welcome Page, select Targets, then select Middleware.
In the Targets table, select your WebLogic domain. If prompted, enter your user credentials to log in to the WebLogic domain.
In the Target Navigation pane, select the cluster you want to configure.
From the WebLogic Cluster menu, select Administration, then select Singleton Services.
In the Singleton Services table, select the singleton service you want to configure.
Select Notes.
On the Notes page, enter your notes.
For more information about these fields, see Configuration Options.
Click Save.
Job scheduling makes Java CommonJ timers cluster-aware and provides the ability to execute jobs periodically anywhere in a cluster without dependency on a particular server instance.
To configure job scheduling in a cluster:
From the Welcome Page, select Targets, then select Middleware.
In the Targets table, select your WebLogic domain. If prompted, enter your user credentials to log in to the WebLogic domain.
In the Target Navigation pane, select the cluster you want to configure.
From the WebLogic Cluster menu, select Administration, then select Scheduling.
From the Scheduling page, you can define configuration settings that specify how information is shared across servers in a cluster.
In the Data Source for Job Scheduler field, select the data source to use.
In the Job Scheduler Table Name field, enter a table name to use for storing timers active with the job scheduler.
Click Save.
For more information, see Configuration Options.
To configure overload for a cluster:
From the Welcome Page, select Targets, then select Middleware.
In the Targets table, select your WebLogic domain. If prompted, enter your user credentials to log in to the WebLogic domain.
In the Target Navigation pane, select the cluster you want to configure.
From the WebLogic Cluster menu, select Administration, then select Overload.
From the Overload page, you can configure the cluster-wide defaults that control how WebLogic Server instances in this cluster should react in the case of an overload or failure condition. The settings you can define include:
Shared Capacity for Work Managers
Failure Action
Panic Action
Free Memory Percent High Threshold
Free Memory Percent Low Threshold
Max Stuck Thread Time
Stuck Thread Count
For more information about these fields, see Configuration Options.
Click Save.
WebLogic Server provides a self-health monitoring capability to improve the reliability and availability of servers in a WebLogic Server domain. Selected subsystems within each server instance monitor their health status based on criteria specific to the subsystem
To configure health monitoring characteristics for a cluster:
From the Welcome Page, select Targets, then select Middleware.
In the Targets table, select your WebLogic domain. If prompted, enter your user credentials to log in to the WebLogic domain.
In the Target Navigation pane, select the cluster you want to configure.
From the WebLogic Cluster menu, select Administration, then select Health Monitoring.
From the Health Monitoring page, you can configure health monitoring characteristics for this cluster, such as:
Inter-Cluster Comm Link Health Check Interval
Health Check Interval
Health Check Periods Until Fencing
Fencing Grace Period
For more information about these fields, see Configuration Options.
Click Save.
To configure HTTP settings for a cluster:
From the Welcome Page, select Targets, then select Middleware.
In the Targets table, select your WebLogic domain. If prompted, enter your user credentials to log in to the WebLogic domain.
In the Target Navigation pane, select the cluster you want to configure.
From the WebLogic Cluster menu, select Administration, then select HTTP.
From the HTTP page, you can define the HTTP settings for this cluster, such as:
Frontend Host
Frontend HTTP Port
Frontend HTTPS Port
For more information about these fields, see Configuration Options.
Click Save.
To configure Coherence settings for a cluster:
From the Welcome Page, select Targets, then select Middleware.
In the Targets table, select your WebLogic domain. If prompted, enter your user credentials to log in to the WebLogic domain.
In the Target Navigation pane, select the cluster you want to configure.
From the WebLogic Cluster menu, select Administration, then select Coherence.
From the Coherence page, you can select the Coherence cluster you want to use for this cluster and define settings such as:
Local Storage Enabled
Coherence Web Local Storage Enabled
For more information about these fields, see Configuration Options.
Click Save.
To create notes for cluster configuration:
From the Welcome Page, select Targets, then select Middleware.
In the Targets table, select your WebLogic domain. If prompted, enter your user credentials to log in to the WebLogic domain.
In the Target Navigation pane, select the cluster you want to configure.
From the WebLogic Cluster menu, select Administration, then select Notes.
On the Notes page, enter your notes.
Click Save.
For more information, see Configuration Options.