Servers: Configuration: Migration
Configuration Options Related Tasks Related Topics
If a clustered server fails, WebLogic Server can automatically restart (migrate) the server and its services on another machine. Alternatively, you can configure options for the JMS-related services (such as JMS servers, SAF agents, path service, and custom persistent stores) and the JTA Transaction Recovery Service on this server so that they can be manually migrated to another server. You can also specify to have the JTA Transaction Recovery Service automatically migrated to another server.
Use this page to enable server migration or to configure services-only migration.
Name Description Candidate Machines
Limits the list of candidate machines that the cluster specifies. (Requires you to enable this server for automatic migration and to configure the cluster with a set of candidate machines.)
If this server fails and if it is enabled for automatic migration, Node Manager automatically restarts it. By default, Node Manager restarts the server on any of the candidate machines that the cluster specifies (in order of preference that you configured in the cluster). To change the default, you use this server's list of candidate machines to create a subset of the cluster-wide candidates. You can also change the order of preference.
Automatic Server Migration Enabled
Specifies whether Node Manager can automatically restart this server and its services on another machine if the server fails.
JMS Service Candidate Servers
Select servers in the cluster to use as a backup for this server's JMS-related services, such as JMS servers, SAF agents, path service, and WebLogic persistent stores.
JTA Migration Policy
Defines the type of migration policy to use for the services hosted by this migratable target. Valid options are:
Manual Service Migration Only
Indicates that no automatic migration of services hosted by this migratable target will occur.
Auto-Migrate Exactly-Once Services
Indicates that if at least one Managed Server in the candidate server list is running, the services hosted by this migratable target will be active somewhere in the cluster if servers should fail or are administratively shut down (either gracefully or forcibly). For example, it is a recommended best practice to use this policy when a migratable target hosts a path service, so if its preferred server fails or is shut down, the path service will automatically migrate to another candidate server, and so will always be active in the cluster.
Note This value can lead to target grouping on a server member. For example, if you have five exactly-once migratable targets and only one Managed Server is started in the cluster, then all five targets will be activated on that server.
Auto-Migrate Failure-Recovery Services
Indicates that the services hosted by this migratable target will only start if the migratable target's User Preferred Server (UPS) is started. If an administrator manually shuts down the UPS, either gracefully or forcibly, then a failure-recovery service will not migrate. However, if the UPS fails due to an internal error, then the service will be migrated to another candidate server. If such a candidate server is unavailable (due to either a manual shutdown or an internal failure), then the migration framework will first attempt to reactivate the service on its UPS server. If the UPS server is not available at that time, then the service will be migrated to another candidate server.
Auto-Migrate Shutdown-Recovery Services
Indicates that the services hosted by this migratable target will migrate to one of the candidate servers, if server is administratively shut down (either gracefully or forcibly). Once recovery is done, service is migrated back to failed server.
JTA Candidate Servers
Select servers that can access the JTA log files (in the WebLogic default persistent store) for the current server.
To migrate the Transaction Recovery Service from a failed server in a cluster to another server (backup server) in the same cluster, the backup server must have access to the transaction log files from the failed server. WebLogic Server uses the WebLogic default persistent store to store transaction log files. Therefore, you must configure the default persistent store to store its data files in a file system on a shareable storage solution, such as a Storage Area Network (SAN) device or a dual-ported disk, that is available to both the primary server and the server that will act as its backup. When using the automatic service migration option, the default persistent store cannot be shared by JTA and other migratable services; only JTA and other non-migratable services can share the same default persistent store.
Pre-Migration Script Path
Specifies the path to the pre-migration script to run before a migratable target is actually activated. The script must be in the
Before the migratable target is activated, if there is a script specified, and Node Manager is available, then the script will run. Specifying a script without an available Node Manager will result in an error upon migration.
If the script fails or cannot be found, migration will not proceed on the current server, and will be tried on the next suitable server. This could be the next server in the candidate server list, or in the cluster, if there is no candidate server list.
Post-Migration Script Path
Specifies the path to the post-migration script to run after a migratable target is fully deactivated. The script must be in the
After the migratable target is deactivated, if there is a script specified, and Node Manager is available, then the script will run. Specifying a script without an available Node Manager will result in an error upon migration.
Post-Migration Script Failure Cancels Automatic Migration
Specifies whether or not a failure during execution of the post-deactivation script is fatal to the migration.
If it is fatal, the migratable target will not be automatically migrated until an administrator manually migrates it to a server, thus reactivating it.
Note: Enabling this value will result in weakening the exactly-once guarantee. It is provided to prevent more dangerous data corruption if the post-deactivation script fails. Also if this value is enabled, then the script may be called more than once by the migration framework after the Migratable Target is deactivated or the server or machine hosting the Migratable Target crashed or is network partitioned. The script is expected not to return different exit values when invoked multiple times in such scenarios.
Allow Post-Migration Script to Run On a Different Machine
Specifies whether or not the post-deactivation script is allowed to run on a different machine.
Normally, when auto migration occurs, the post-deactivation script will be run on the service's current location, and the pre-activation script on the service's new location. If the current location is unreachable for some reason, this value will be checked to see if it is safe to run it on the service's new machine.
This is useful if the post-deactivation script controls access to a networked resource and does not need any data from the current machine.
Enable Strict Ownership Check
Whether continue to boot if cannot find the current owner of TRS to do failback. This attribute is only meaningful for servers in cluster.
If true: server will fail to boot under this situation.
If false: server will continue to boot without trying to do failback.
- Start and stop servers
- Assign server instances to clusters
- Configure server migration in a cluster
- Configure cross-cluster replication
- Configure JMS Services for migration and high availability
- Configure the JTA Transaction Recovery Service for migration