Use this task to configure a backup cluster that handles
Enterprise JavaBeans (EJB) requests if
the primary cluster fails.
Before you begin
Before you begin, create two clusters that are able to
provide backup for each other. The objects and resources available
in the primary cluster must also be available in the backup cluster.
You must use the same cluster name, install the same applications,
use the same application names, and define the same resources in
the backup cluster as in the primary cluster.
The primary cluster
and the backup cluster must reside in separate cells because a cluster
must have a unique name within a cell.
About this task
Perform this task to create a backup cluster for your
EJB clusters. When all the servers in the primary cluster fail, work
is not halted because the backup cluster can continue serving requests
for EJB work.
To configure a backup cluster, specify a name
and a port. The port is called a domain bootstrap address and consists
of a bootstrap host and port. The bootstrap host is the host that
contains the deployment manager in which the backup cluster is configured.
The bootstrap port is equal to the bootstrap port for the same deployment
manager.
The primary cluster and the backup cluster must reside
in separate cells. The bootstrap host and port for the backup cluster
determine which cell contains the backup cluster.
Procedure
- Determine the bootstrap host and port of the backup cluster.
- Connect the administrative console for the deployment
manager that contains the backup cluster.
- Click . The host and port for the BOOTSTRAP_ADDRESS instance
is the host and port that the backup cluster uses. Remember these
values for when you configure the primary cluster.
- Connect the administrative console to the deployment manager
that contains the primary cluster. Click cluster_name > Backup cluster.
- Ensure that the name of the backup cluster is the same
as the primary cluster.
- Click Domain bootstrap address. Specify the backup
cluster deployment manager bootstrap host and port in the Host and Port fields. Click OK. The bootstrap host and
port combined define a bootstrap address for the deployment manager. On the Domain Bootstrap Address page, use the Configuration tab to statically define the backup cluster; the static value is
consumed each time the deployment manager starts. You can use the Runtime tab to define the backup cluster during run time only;
when the deployment manager stops, the run-time backup cluster information
is discarded.
- Click OK.
- Configure a core group bridge between each of the cluster
core groups. Use an access point group to join the two
core groups. In the deployment manager for the primary cell, configure
an access point group that has a peer access point that refers to
the core group access point in the backup cell. In the deployment
manager for the backup cell, create an access point group that has
the same name as the access point group that you created in the primary
cell. Add a peer access point that refers to the core group access
point in the primary cell. See the topic on configuring the core group
bridge service for more information.
Tip: If you are configuring a V5.x cluster to back up a cluster that is
on the current release, do not configure the core group bridge service.
Core groups are not supported in V5.x. Therefore, the V5.x cluster
does not belong to a core group. The backup cluster still functions
using only the domain bootstrap address.
- Save the configuration.
Results
The backup cluster completes EJB requests when the primary
cluster fails.
What to do next
If you experience problems when configuring
your backup cluster, read the topic on what to do if the workload
is not getting distributed.