ClusterMBean
Overview | Related MBeans | Attributes | Operations
Overview
This bean represents a cluster in the domain. Servers join a cluster by calling ServerMBean.setCluster with the logical name of the cluster. A configuration may define zero or more clusters. They may be looked up by logical name. The name of a cluster denotes its logical cluster name.
Fully Qualified Interface Name If you use the getMBeanInfo operation in MBeanTypeServiceMBean, supply the following value as this MBean's fully qualified interface name:
weblogic.management.configuration.ClusterMBean
Factory Methods No factory methods. Instances of this MBean are created automatically.
Related MBeans
This section describes attributes that provide access to other MBeans. For more information about the MBean hierarchy, refer to WebLogic Server MBean Data Model.
CandidateMachinesForMigratableServers
The set of machines (and order of preference) on which Node Manager will restart failed servers. (Requires you to enable each server for automatic migration.)
Each server can specify a subset of these cluster-wide candidates, which limits the machines on which the server can be restarted. Servers can also specify their own order of preference.
For more information, see:
Privileges Read/Write Type MachineMBean[] Relationship type: Reference. Redeploy or Restart required Changes take effect after you redeploy the module or restart the server.
DatabaseLessLeasingBasis
Get attributes associated with database less leasing basis used for server migration and singleton services.
Factory Methods No explicit creator method. The child shares the lifecycle of its parent. Privileges Read only Type DatabaseLessLeasingBasisMBean Relationship type: Containment.
DataSourceForAutomaticMigration
The data source used by servers in the cluster during migration. (You must configure each Migratable Server within the cluster to use this data source.)
Privileges Read/Write Type JDBCSystemResourceMBean Relationship type: Reference. Redeploy or Restart required Changes take effect after you redeploy the module or restart the server.
DataSourceForJobScheduler
Data source required to support persistence of jobs scheduled with the job scheduler
Privileges Read/Write Type JDBCSystemResourceMBean Relationship type: Reference. Redeploy or Restart required Changes take effect after you redeploy the module or restart the server.
DataSourceForSessionPersistence
To support HTTP Session failover across data centers, requires a datasource to dump session state on disk.
Privileges Read/Write Type JDBCSystemResourceMBean Relationship type: Reference. Redeploy or Restart required Changes take effect after you redeploy the module or restart the server.
MigratableTargets
Returns all the MigratableTargets for this cluster
Privileges Read only Type MigratableTargetMBean[] Relationship type: Reference.
OverloadProtection
Get attributes related to server overload protection. The default values for all cluster members are set here. Individual servers can override them as needed.
Factory Methods No explicit creator method. The child shares the lifecycle of its parent. Privileges Read only Type OverloadProtectionMBean Relationship type: Containment.
Servers
The servers which have declared membership in this cluster.
Privileges Read only Type ServerMBean[] Relationship type: Reference.
Attributes
This section describes the following attributes:
AdditionalAutoMigrationAttempts
A migratable server could fail to come up on every possible configured machine. This attribute controls how many further attempts, after the first one, should be tried. Note that each attempt specified here indicates another full circut of migrations amongst all the configured machines. So for a 3-server cluster, and the default value of 3, a total of 9 migrations will be attempted. If it is set to -1, migrations will go on forever until the server starts.
Privileges Read/Write Type int Default Value 3
AsyncSessionQueueTimeout
Interval in seconds until the producer thread will wait for the AsyncSessionQueue to become unblocked. Should be similar to the RequestTimeOut as that will determine the longest that the queue should remain full.
Privileges Read/Write Type int Default Value 30
AutoMigrationTableName
Return the name of the table to be used for server migration.
Privileges Read/Write Type java.lang.String Default Value ACTIVE
CachingDisabled
Private property that disables caching in proxies.
Privileges Read only Type boolean Redeploy or Restart required Changes take effect after you redeploy the module or restart the server.
ClientCertProxyEnabled
Whether to honor the WL-Proxy-Client-Cert header coming with the request or not.
For more information, see:
Privileges Read/Write Type boolean
ClusterAddress
The address that forms a portion of the URL a client uses to connect to this cluster, and that is used for generating EJB handles and entity EJB failover addresses. (This address may be either a DNS host name that maps to multiple IP addresses or a comma-separated list of single address host names or IP addresses.)
Defines the address to be used by clients to connect to this cluster. This address may be either a DNS host name that maps to multiple IP addresses or a comma separated list of single address host names or IP addresses. If network channels are configured, it is possible to set the cluster address on a per channel basis.
For more information, see:
Privileges Read/Write Type java.lang.String
ClusterBroadcastChannel
Specifies the channel used to handle communications within a cluster. If no channel is specified the default channel is used.
ClusterBroadcastChannel is only are supported if the unicast messaging type is used.
Privileges Read/Write Type java.lang.String
ClusterMessagingMode
Specifies the messaging type used in the cluster.
Multicast messaging, the default, is provided for backwards compatibility.
Unicast message is recommended for new clusters.
Privileges Read/Write Type java.lang.String Default Value multicast Legal Values
- multicast
- unicast
ClusterType
Optimizes cross-cluster replication for the type of network that servers in the clusters use for administrative communication.
To enhance the reliability of HTTP sessions, you can configure servers in one cluster to replicate the session data to servers in a different cluster. In such an environment, configure the clusters to be one of the following types:
man
if the clustered servers can send their data through a metro area network (man) in which latency is negligible. With this ClusterType value, servers replicate session state synchronously and in memory only. For example, when serverA in cluster1 starts an HTTP session, its backup server, serverB in cluster2, immediately replicates this session in memory to Server B.
wan
if the clusters are far apart or send their data through a wide area network (wan) that experiences significant network latency. With this ClusterType value, a server replicates session state synchronously to the backup server in the same cluster and asynchronously to a server in the remote cluster. For example, when serverA in cluster1 starts an HTTP session, it sends the data to serverB in cluster1 and then asynchronously sends data to serverX in cluster 2. ServerX will persist the session state in the database.
If you persist session data in a replicating database, and if you prefer to use the database to replicate the data instead of WebLogic Server, choose a cluster type of
wan and leave the remote cluster address undefined. WebLogic Server saves the session data to the local database and assumes that the database replicates data as needed.
Privileges Read/Write Type java.lang.String Default Value none Legal Values
- none
- wan
- man
DefaultLoadAlgorithm
The algorithm to be used for load-balancing between replicated services if none is specified for a particular service. The round-robin algorithm cycles through a list of WebLogic Server instances in order. Weight-based load balancing improves on the round-robin algorithm by taking into account a pre-assigned weight for each server. In random load balancing, requests are routed to servers at random.
Defines the algorithm to be used for load-balancing between replicated services if none is specified for a particular service.
Privileges Read/Write Type java.lang.String Default Value round-robin Legal Values
- round-robin
- weight-based
- random
- round-robin-affinity
- weight-based-affinity
- random-affinity
FencingGracePeriodMillis
During automatic migration, if the Cluster Master determines a server to be dead, it waits for this period of time (in milliseconds) before the Cluster Master migrates the service to another server in the cluster.
Privileges Read/Write Type int Default Value 30000
FrontendHost
The name of the host to which all redirected URLs will be sent.
Sets the HTTP FrontendHost for the default webserver (not virtual hosts) for all the servers in the cluster. Provides a method to ensure that the webapp will always have the correct HOST information, even when the request is coming through a firewall or a proxy. If this parameter is configured, the HOST header will be ignored and the information in this parameter will be used in its place, when constructing the absolute urls for redirects.
For more information, see:
Privileges Read/Write Type java.lang.String
FrontendHTTPPort
The name of the HTTP port to which all redirected URLs will be sent.
Sets the FrontendHTTPPort for the default webserver (not virtual hosts) for all the servers in the cluster. Provides a method to ensure that the webapp will always have the correct PORT information, even when the request is coming through a firewall or a proxy. If this parameter is configured, the HOST header will be ignored and the information in this parameter will be used in its place, when constructing the absolute urls for redirects.
For more information, see:
Privileges Read/Write Type int Default Value 0
FrontendHTTPSPort
The name of the secure HTTP port to which all redirected URLs will be sent.
Sets the FrontendHTTPSPort for the default webserver (not virtual hosts) for all the servers in the cluster. Provides a method to ensure that the webapp will always have the correct PORT information, even when the request is coming through a firewall or a proxy. If this parameter is configured, the HOST header will be ignored and the information in this parameter will be used in its place, when constructing the absolute urls for redirects.
For more information, see:
Privileges Read/Write Type int Default Value 0
GreedySessionFlushInterval
Interval in seconds until HTTP Sessions are periodically flushed to secondary server.
Privileges Read/Write Type int Default Value 10
HealthCheckIntervalMillis
Interval in milliseconds at which Migratable Servers and Cluster Masters prove their liveness via the database.
Privileges Read/Write Type int Default Value 10000
HealthCheckPeriodsUntilFencing
Maximum number of periods that a cluster member will wait before timing out a Cluster Master and also the maximum number of periods the Cluster Master will wait before timing out a Migratable Server.
Privileges Read/Write Type int Default Value 3 Minimum value 2
HttpTraceSupportEnabled
Returns the value of HttpTraceSupportEnabled.
For more information, see:
Privileges Read/Write Type boolean
IdlePeriodsUntilTimeout
Maximum number of periods that a cluster member will wait before timing out a member of a cluster.
Maximum number of periods that a cluster member will wait before timing out a member of a cluster.
Privileges Read/Write Type int Default Value 3 Minimum value 3
InterClusterCommLinkHealthCheckInterval
If the cluster link between two clusters goes down, a trigger will run to periodically to see if the link is restored. The duration is specified in milliseconds.
Privileges Read/Write Type int Default Value 30000
JobSchedulerTableName
The table name to use for storing timers active with the job scheduler
Privileges Read/Write Type java.lang.String Default Value weblogic_timers
MBeanInfo
Returns the MBean info for this MBean.
Deprecated.
Privileges Read only Type javax.management.MBeanInfo Redeploy or Restart required Changes take effect after you redeploy the module or restart the server.
MemberWarmupTimeoutSeconds
Maximum number of seconds that a cluster member will wait to discover and synchronize with other servers in the cluster. Normally, the member will be able to sync in 30 seconds. If the value of this attribute is higher, that does not necessarily mean that it will take longer for the member to warmup. Instead it defines an upper bound on the time that a server will wait to sync with the servers that it has discoverred. If the value is set 0, servers will not attempt to discover other running server in the cluster during server initialization
Privileges Read/Write Type int Default Value 30 Minimum value 0
MigrationBasis
Controls the mechanism used for server and service migration.
- Database
-- Requires the availability of a high-availability database, such as Oracle RAC, to store leasing information.
- Consensus
-- Stores the leasing information in-memory within a cluster member. This option requires Node Manager to be configured and running.
Note: Within a WebLogic Server installation, you can only use one type of leasing. Although it is possible to implement multiple features that use leasing within your environment, each must use the same kind of leasing.
Privileges Read/Write Type java.lang.String Default Value database Legal Values
- database
- consensus
MillisToSleepBetweenAutoMigrationAttempts
Controls how long of a pause there should be between the migration attempts described in getAdditionalAutoMigrationAttempts(). Note that this delay only happens when the server has failed to come up on every machine.
For more information, see:
Privileges Read/Write Type long Default Value 180000
MulticastAddress
The multicast address used by cluster members to communicate with each other.
The valid range is from from 224.0.0.0 to 239.255.255.255. The default value used by WebLogic Server is 239.192.0.0. You should avoid using multicast addresses in the range x.0.0.1
This address should be unique to this cluster and should not be shared by other applications.
For more information, see:
Privileges Read/Write Type java.lang.String Default Value 239.192.0.0
MulticastBufferSize
The multicast socket send/receive buffer size (at least 64 kilobytes).
Returns the multicast socket send/receive buffer size.
Privileges Read/Write Type int Default Value 64 Minimum value 64
MulticastDataEncryption
Enables multicast data to be incrypted. Only the multicast data is encrypted. Multicast header information is not encrypted.
Privileges Read/Write Type boolean
MulticastPort
The multicast port (between 1 and 65535) used by cluster members to communicate with each other.
Defines the multicast port used by cluster members to communicate with each other.
For more information, see:
Available Since Release 7.0.0.0 Privileges Read/Write Type int Default Value 7001 Minimum value 1 Maximum value 65535
MulticastSendDelay
The amount of time (between 0 and 250 milliseconds) to delay sending message fragments over multicast in order to avoid OS-level buffer overflow.
Defines the number of milliseconds to delay sending message fragments over multicast in order to avoid OS-level buffer overflow.
Privileges Read/Write Type int Default Value 3 Minimum value 0 Maximum value 250
MulticastTTL
The number of network hops (between 1 and 255) that a cluster multicast message is allowed to travel.
Defines the number of network hops that a cluster multicast message is allowed to travel. 1 restricts the cluster to one subnet.
Privileges Read/Write Type int Default Value 1 Minimum value 1 Maximum value 255
Name of
The user-specified name of this MBean instance.
This name is included as one of the key properties in the MBean's
javax.management.ObjectName:
Name of=user-specified-name
Privileges Read/Write Type java.lang.String
Notes
Optional information that you can include to describe this configuration.
WebLogic Sever saves this note in the domain's configuration file (
config.xml) as XML PCDATA. All left angle brackets (<) are converted to the XML entity
<. Carriage returns/line feeds are preserved.
- Note:
If you create or edit a note from the Administration Console, the Administration Console does not preserve carriage returns/line feeds.
Privileges Read/Write Type java.lang.String
NumberOfServersInClusterAddress
Number of servers to be listed from this cluster when generating a cluster address automatically. This setting has no effect if Cluster Address is explicitly set.
For more information, see:
Privileges Read/Write Type int Default Value 3
ObjectName
Returns the ObjectName under which this MBean is registered in the MBean server.
Deprecated.
Privileges Read only Type weblogic.management.WebLogicObjectName Redeploy or Restart required Changes take effect after you redeploy the module or restart the server.
Parent
Return the immediate parent for this MBean
Privileges Read/Write Type
PersistSessionsOnShutdown
When shutting down servers, sessions are not updated. If the primary and secondary servers of a session are shut down with no session updates, the session will be lost. Turning on PersistSessionsOnShutdown will save any active sessions to the database specified in ClusterMBean#getDataSourceForSessionPersistence() when a server is shutdown. The sessions will not be written at any other time. (For example, they are not saved via this mechanism if there is a server crash.)
This attribute is applicable both to session persistence on server shutdown or session persistence across a WAN.
Rolling upgrade can potential have a bad interaction with traditional in-memory session replication. As managed servers are shutdown and upgraded, in-memory servlet sessions will be lost if both primary and secondary are rebooted before a new request arrives for the session.
Privileges Read/Write Type boolean
Registered
Returns false if the the MBean represented by this object has been unregistered.
Deprecated.
Privileges Read only Type boolean Redeploy or Restart required Changes take effect after you redeploy the module or restart the server.
RemoteClusterAddress
Set the foreign cluster. Cluster infrastructure uses this address to connect to foreign cluster for HTTP Session WAN/MAN failover.
Privileges Read/Write Type java.lang.String
ReplicationChannel
The channel name to be used for replication traffic. Cluster infrastructure uses this channel to send updates for HTTP sessions and stateful session beans. If none is set then the default channel will be used.
In order for this feature to work, the named channel must exist on all members of the cluster and must be configured to use the same protocol. It is valid for the selected channel to be configured to use a secure protocol.
For more information, see:
Privileges Read/Write Type java.lang.String Default Value ReplicationChannel
ReplicationTimeoutEnabled
Indicates if timeout should be applied to session replication calls.
Privileges Read/Write Type boolean Default Value true
SecureReplicationEnabled
Servers in a cluster replicates session data. If replication channel is defined then the session data will be sent using the replication channel protocol and secured replication settings will be ignored. If no replication channel is defined and secured replication is enabled then session data for in-memory replication will be sent over SSL using default secured channel. However, this added security for replication traffic comes with a significant cluster performance degradation. It should only be enabled if security is of greater concern than the performance degradation.
Available Since Release 7.0.8.0 Privileges Read/Write Type boolean
ServiceAgeThresholdSeconds
The number of seconds (between 0 and 65534) by which the age of two conflicting services must differ before one is considered older than the other.
Defines the number of seconds by which the age of two conflicting services must differ before one is considered older than the other.
Privileges Read/Write Type int Default Value 180 Minimum value 0 Maximum value 65534
SessionFlushInterval
Interval in seconds until HTTP Sessions are periodically flushed to the backup cluster to dump session state on disk.
Privileges Read/Write Type int Default Value 180
SessionFlushThreshold
When number of sessions to be flushed reaches this threshold limit, sessions will be flushed to the backup cluster before the flush interval. This helps the server to flush sessions faster under load.
Privileges Read/Write Type int Default Value 100
Type
Returns the type of the MBean.
Privileges Read only Type java.lang.String Redeploy or Restart required Changes take effect after you redeploy the module or restart the server.
WANSessionPersistenceTableName
Return the name of the table to be used for WAN session persistence.
Privileges Read/Write Type java.lang.String Default Value WLS_WAN_PERSISTENCE_TABLE
WeblogicPluginEnabled
Whether the proprietary WL-Proxy-Client-IP header should be used. (This needed only when WebLogic plugins are configured.)
Gets the weblogicPluginEnabled attribute of the ClusterMBean object
For more information, see:
Privileges Read/Write Type boolean
Operations
This section describes the following operations:
freezeCurrentValue
If the specified attribute has not been set explicitly, and if the attribute has a default value, this operation forces the MBean to persist the default value.
Unless you use this operation, the default value is not saved and is subject to change if you update to a newer release of WebLogic Server. Invoking this operation isolates this MBean from the effects of such changes.
- Note:
To insure that you are freezing the default value, invoke the
restoreDefaultValue operation before you invoke this.
This operation has no effect if you invoke it on an attribute that does not provide a default value or on an attribute for which some other value has been set.
Deprecated.
9.0.0.0
Operation Name "freezeCurrentValue"
Parameters Object [] { attributeName }
where:
attributeName is an object of type
java.lang.String that specifies:
attributeName
Signature String [] { "java.lang.String" }
Returns void
Exceptions
javax.management.AttributeNotFoundException
javax.management.MBeanException
isSet
Returns true if the specified attribute has been set explicitly in this MBean instance.
Operation Name "isSet"
Parameters Object [] { propertyName }
where:
propertyName is an object of type
java.lang.String that specifies:
property to check
Signature String [] { "java.lang.String" }
Returns boolean
kill
Used to force a Shutdown of all the servers belonging to the Cluster.
Operation Name "kill"
Parameters null
Signature null
Returns HashMap
restoreDefaultValue
If the specified attribute has a default value, this operation removes any value that has been set explicitly and causes the attribute to use the default value.
Default values are subject to change if you update to a newer release of WebLogic Server. To prevent the value from changing if you update to a newer release, invoke the
freezeCurrentValue operation.
This operation has no effect if you invoke it on an attribute that does not provide a default value or on an attribute that is already using the default.
Deprecated.
9.0.0.0
Operation Name "restoreDefaultValue"
Parameters Object [] { attributeName }
where:
attributeName is an object of type
java.lang.String that specifies:
attributeName
Signature String [] { "java.lang.String" }
Returns void
Exceptions
javax.management.AttributeNotFoundException
start
Used to start all the servers belonging to the Cluster. HashMap contains references to TaskRuntimeMBeans corresponding to each server in the Cluster, keyed using the server name.
Operation Name "start"
Parameters null
Signature null
Returns HashMap
unSet
Restore the given property to its default value.
Operation Name "unSet"
Parameters Object [] { propertyName }
where:
propertyName is an object of type
java.lang.String that specifies:
property to restore
Signature String [] { "java.lang.String" }
Returns void