weblogic.management.configuration
Interface MigratableTargetMBean

All Superinterfaces:

ConfigurationMBean, TargetMBean

All Known Subinterfaces:

JTAMigratableTargetMBean

public interface MigratableTargetMBean
extends TargetMBean

A target that is suitable for services that shall be active on at most one server of a cluster at a time.

Deprecation of MBeanHome and Type-Safe Interfaces

This is a type-safe interface for a WebLogic Server MBean, which you can import into your client classes and access through weblogic.management.MBeanHome. As of 9.0, the MBeanHome interface and all type-safe interfaces for WebLogic Server MBeans are deprecated. Instead, client classes that interact with WebLogic Server MBeans should use standard JMX design patterns in which clients use the javax.management.MBeanServerConnection interface to discover MBeans, attributes, and attribute types at runtime. For more information, see "Developing Manageable Applications with JMX."

Since:

7.0.0.0

See Also:

TargetMBean, SingletonServiceBaseMBean

DEFAULT_MIGRATABLETARGET_SUFFIX

static final String DEFAULT_MIGRATABLETARGET_SUFFIX

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Constant Field Values

NONE

static final String NONE

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Constant Field Values

EXACTLY_ONCE

static final String EXACTLY_ONCE

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Constant Field Values

FAILURE_RECOVERY

static final String FAILURE_RECOVERY

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Constant Field Values

getConstrainedCandidateServers

ServerMBean[] getConstrainedCandidateServers()

The (user-restricted) list of servers that can host the migratable services deployed to this migratable target. The migratable service will not be allowed to migrate to a server that is not in the returned list of servers.

For example, this feature may be used to configure two servers that have access to a dual-ported ported disk. All servers in this list must be part of the cluster that is associated with the migratable target.

Returns:

The constrainedCandidateServers value

setConstrainedCandidateServers

void setConstrainedCandidateServers(ServerMBean[] constrainedCandidateServers)
                                    throws InvalidAttributeValueException

All constrained candiate servers must belong to the same cluster.

Parameters:

constrainedCandidateServers - The new constrainedCandidateServers value

Throws:

InvalidAttributeValueException

addConstrainedCandidateServer

boolean addConstrainedCandidateServer(ServerMBean constrainedCandidateServer)
                                      throws InvalidAttributeValueException

Parameters:

constrainedCandidateServer - The feature to be added to the ConstrainedCandidateServer attribute

Returns:

Throws:

InvalidAttributeValueException

removeConstrainedCandidateServer

boolean removeConstrainedCandidateServer(ServerMBean constrainedCandidateServer)
                                         throws InvalidAttributeValueException

Parameters:

constrainedCandidateServer -

Returns:

Throws:

InvalidAttributeValueException

setUserPreferredServer

void setUserPreferredServer(ServerMBean t)

Parameters:

t - The new userPreferredServer value

getCluster

ClusterMBean getCluster()

Returns the cluster this singleton service is associated with.

Returns:

The cluster value

setCluster

void setCluster(ClusterMBean cluster)

Set the cluster this singleton service is associated with.

Parameters:

cluster - The new cluster value

getAllCandidateServers

ServerMBean[] getAllCandidateServers()

The list of servers that are candiates to host the migratable services deployed to this migratable target. If the constrainedCandidateServers list is empty, all servers in the cluster are returned. If the constrainedCandidateServers list is not empty, only those servers will be returned. The user-preferred server will be the first element in the list.

Returns:

The allCandidateServers value

setAllCandidateServers

void setAllCandidateServers(ServerMBean[] servers)

Parameters:

servers - The new allCandidateServers value

getMigrationPolicy

String getMigrationPolicy()

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.

Returns:

MigrationPolicy, the name of the auto migration policy chosen for this target

See Also:

MigratableTargetMBean.setUserPreferredServer(weblogic.management.configuration.ServerMBean)

Default Value:

MigratableTargetMBean.NONE

Valid Values:

MigratableTargetMBean.NONE, MigratableTargetMBean.EXACTLY_ONCE, MigratableTargetMBean.FAILURE_RECOVERY

setMigrationPolicy

void setMigrationPolicy(String migrationPolicyName)

Sets the value of the MigrationPolicy attribute.

Parameters:

migrationPolicyName - the name of the auto migration policy chosen for this target

See Also:

MigratableTargetMBean.getMigrationPolicy()

getPreScript

String getPreScript()

Specifies the path to the pre-migration script to run before a migratable target is actually activated. The script must be in the MIDDLEWARE_HOME/user_projects/domains/mydomain/bin/service_migration directory.

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.

setPreScript

void setPreScript(String filePath)

Sets the value of the PreScript attribute.

Parameters:

filePath - file name and relative path for pre script

See Also:

MigratableTargetMBean.getPreScript()

getPostScript

String getPostScript()

Specifies the path to the post-migration script to run after a migratable target is fully deactivated. The script must be in the MIDDLEWARE_HOME/user_projects/domains/mydomain/bin/service_migration directory.

After the migratable target is deactivated, if there is a script specified, and Node Manager is available, then the sript will run. Specfiying a script without an available Node Manager will result in an error upon migration.

setPostScript

void setPostScript(String filePath)

Sets the value of the PostScript attribute.

Parameters:

filePath - file name and relative path for post script

See Also:

MigratableTargetMBean.getPostScript()

isPostScriptFailureFatal

boolean isPostScriptFailureFatal()

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.

Returns:

boolean indicating if the failure of a post-deactivation script is fatal to the migration or not

Default Value:

true

setPostScriptFailureFatal

void setPostScriptFailureFatal(boolean isFatal)

Sets the value of the PostScriptFailureFatal attribute.

Parameters:

isFatal - indicating if the failure of a post-deactiation script is fatal to the migration or not

See Also:

MigratableTargetMBean.isPostScriptFailureFatal()

isNonLocalPostAllowed

boolean isNonLocalPostAllowed()

Specifies whether or not the post-deactivation script is allowed to run on a different machine.

Normally, when automigration 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.

Returns:

boolean indicating whether to run the post-deactivation script on a different machine if the former host machine is not reachable.

Default Value:

false

setNonLocalPostAllowed

void setNonLocalPostAllowed(boolean allowNonLocalPost)

Sets the value of the NonLocalPostAllowed attribute.

Parameters:

allowNonLocalPost - indicating whether to run the post-deactivation script on a different machine if the former host machine is not reachable

See Also:

MigratableTargetMBean.isNonLocalPostAllowed()

getRestartOnFailure

boolean getRestartOnFailure()

Specifies whether or not a failed service will first be deactivated and reactivated in place, instead of being migrated.

The number of restart attempts is controlled by MigratableTargetMBean.getNumberOfRestartAttempts(). Once these restart attempts are exhausted, the service will migrate. A restarting migratable target will deactivate all services on it in order, then reactivate them all.

Returns:

Default Value:

false

setRestartOnFailure

void setRestartOnFailure(boolean restartOnFailure)

Sets the value of the RestartOnFailure attribute.

Parameters:

restartOnFailure -

See Also:

MigratableTargetMBean.getRestartOnFailure()

getSecondsBetweenRestarts

int getSecondsBetweenRestarts()

Specifies how many seconds to wait in between attempts to restart the failed service.

Returns:

Default Value:

30

setSecondsBetweenRestarts

void setSecondsBetweenRestarts(int seconds)

Sets the value of the SecondsBetweenRestarts attribute.

Parameters:

seconds - to pause between migratable target restart attempts

See Also:

MigratableTargetMBean.getSecondsBetweenRestarts()

getNumberOfRestartAttempts

int getNumberOfRestartAttempts()

Specfies how many restart attempts to make before migrating the failed service.

Note that these are consecutive attempts. If the value is set to 6, and the service restart fails 5 times before succeeding, but then fails again later, it will not instantly migrate. Each failure gets its own count of restart attempts.

A value of 0 is identical to setting MigratableTargetMBean.getRestartOnFailure() to false. A value of -1 indicates the service should never be migrated; instead, it will be restarted until it either works or the server shuts down.

Returns:

Default Value:

6

setNumberOfRestartAttempts

void setNumberOfRestartAttempts(int restartAttempts)

Sets the value of the NumberOfRestartAttempts attribute.

Parameters:

restartAttempts -

See Also:

MigratableTargetMBean.getNumberOfRestartAttempts()