Use this task to configure a data replication domain to
transfer data, objects, or events for session manager, dynamic cache,
or stateful session beans. Data replication domains use the data replication
service (DRS), which is an internal product component that performs
replication services, including replicating data, objects, and events
among application servers.
About this task
Use this task to configure
replication, a service
that transfers data, objects, or events among the application servers
in a cluster. Use replication to prevent loss of session data with
session manager, to further improve the performance of the dynamic
cache service, and to provide failover in stateful session beans.
For more information about replication, see
Replication.
Procedure
- Create a replication domain. Use one of the
following methods to create a replication domain:
- Create a replication domain manually.
To create a replication
domain manually without creating a new cluster, click Environment
> Replication domains > New in the administrative console.
On
this page you can specify the properties for the replication domain,
including timeout, encryption, and number of replicas. See Data replication domain settings for
more information about the properties that you can configure for your
replication domain.
- Create a replication domain when you
create a cluster.
To create a replication domain when you create
a cluster, click Servers > Clusters > New in the administrative
console. Enable Create replication domain for this cluster.
The replication domain that is created has the same name as the cluster
and has the default settings for a replication domain. The default
settings for a replication domain are to create a single replica of
each piece of data and to have encryption disabled. To modify the
replication domain properties, click Environment > Replication
domains > replication_domain_name in the administrative
console. See Creating clusters for more information about creating a cluster.
For more information about the replication domain
settings that you can configure in the administrative console, see Data replication domain settings
- Configure the consumers, or the components that use the
replication domains. Dynamic cache, session manager, and
stateful session beans are the three types of replication domain consumers.
Each type of consumer must be configured with a different replication
domain. For example, session manager uses one domain and dynamic cache
uses a different replication domain. However, use one replication
domain if you are configuring HTTP session memory-to-memory replication
and stateful session bean replication. Using one replication domain
in this case ensures that the backup state information of HTTP sessions
and stateful session beans are on the same application servers.
Results
Data is replicating among the application servers in a configured
replication domain.
What to do next
If you select DES or 3DES as the encryption type for a replication
domain, an encryption key is used for the encryption of messages.
At regular intervals, for example once a month, you should go to the Environment
> Replication domains page in the administrative console, and
click Regenerate encryption key to regenerate the key. After
the key is regenerated, you must restart all of the application servers
that are configured as part of the replication domain. Periodically
regenerating the key improves data security.