Multi-broker replication domain settings
Use this page to configure a multi-broker replication domain. This administrative console page applies only to replication domains that were created with a previous version of WebSphere Application Server. Replication domains use the data replication service (DRS).
To view this administrative console page, click Environment > Replication domains > multibroker_replication_domain_name.
An application server that is connected to a replicator within a domain can access the ame set of data sent out by any application server connected to any other replicator (including the same replicator). Data is not shared across replication domains.
Specifies a name for the replication domain. The name must be unique within the cell.
- Request timeout
Number of seconds that a replication domain consumer waits when requesting information from another replication domain consumer before giving up and assuming the information does not exist. The default is 5 seconds.
Data type Integer Units Seconds Default 5
- Encryption type
Specifies the type of encryption used before the object transfers over the network. The options include NONE, DES, TRIPLE_DES. The default is NONE. The DES and TRIPLE_DES options encrypt data sent between WAS processes and secure the network joining the processes.
If you specify DES or TRIPLE_DES, a key for global data replication is generated after you click Apply or OK. When you use the DES or TRIPLE_DES encryption type, click Regenerate encryption key at regular intervals such as monthly because periodically changing the key enhances security.
- DRS partition size
Number of groups into which a replication domain is partitioned. By default, data sent by a WAS process to a replication domain is transferred to all other WebSphere Application Server processes connected to that replication domain. To filter or reduce the number of destinations for the data being sent, partition the replication domain. There should be at least one server listening to every partition. If there are no servers listening on a partition, all the replicas created in that partition are lost because there is no server to cache the objects. The default partition size is 10, and the partition size should be 10 or more to enhance performance.
Partitioning the replication domain is only applicable if you are replicating data to support retrieval of an HTTP session if the process maintaining the HTTP session fails. Partitioning is not supported for sharing of cached data maintained by Web container dynamic caching. As to dynamic caching, all partitions or groups are always active and used for data replication.
When you partition a replication domain, you define the total number of groups or partitions. Use this setting to define the number of groups. Then, when you configure a specific session manager under a Web container or as part of an enterprise application or Web module, select the partition to which that session manager instance listens and from which it accepts data. To specify the groups to which an application server listens, change the settings for affected servers on a session manager page. In addition, you can set a role or runtime mode for a server. This role or mode affects whether a WAS process sends data to the replication domain, receives data, or does both. The default is both to receive and send data.
Data type Integer Default 10
- Single replica
Specifies that a single replication of data is made. Use this option only if you are using session manager with memory to memory replication. Enable this option if you are replicating data to support retrieval of an HTTP session if the process maintaining the HTTP session fails. This option restricts the recipient of the data to a single instance.
Note: Do not enable this option on a domain that is using dynamic cache replication. This setting provides filtering beyond grouping or partitioning. Using this setting, one can choose to have data only sent to one other listening instance in the replication domain.
- Serialization method
Specifies the object serialization method to use when replicating data. An administrative concern with replicating Java objects is locating the class definition, especially in a Java 2, Enterprise Edition (J2EE) environment where class definitions might reside only in certain web modules or enterprise applications. Object serialization methods define whether the processes receiving data also need the class definition.
The options for this setting are OBJECT and BYTES. The default is BYTES.
OBJECT instructs a replicator to write the object directly to the stream. With OBJECT, a replicator must instantiate the object on the receiving side so it must have the class definition.
BYTES instructs a replicator to break down the object into bytes and then send only the bytes across the stream. With BYTES, a replicator does not need to instantiate the object on the receiving side. The BYTES option is useful for failover, where the data is not used at the receiving side and the class definitions do not need to be stored on the receiving side. Or, the option requires that you move class definitions from the Web application class path to the system class path.
- DRS pool size
Specifies the size of the pool of resources allocated for communication with its Java Message Service (JMS) transport. You must configure this number to be the same as the DRS partition size. The default is 10.
Pooling replication resources can enhance the performance of the WebSphere internal data replication service.
- DRS pool connections
Specifies that the domain replication service should create a pool of connections with its Java Message Service (JMS) transport rather than reusing a single connection. You can pool connections when using a single replica or client server environment. You should not pool connections in a peer to peer environment.
The default is to not create a pool of connections for replication.
Replicator entry collection
Multi-broker replication domains
Replicating data with a multi-broker replication domain
WebSphere is a trademark of the IBM Corporation in the United States, other countries, or both.
IBM is a trademark of the IBM Corporation in the United States, other countries, or both.