Installing a service application on a cluster places additional
requirements on you. It is important that you keep these considerations
in mind as you install any service applications on a cluster.
Clusters can provide many benefits to your processing environment
by providing economies of scale to help you balance request workload
across servers and provide a level of availability for clients of
the applications. Consider the following before installing an application
that contains services on a cluster:
- Will users of the application require the processing power and
availability provided by clustering?
If so, clustering is the correct
solution. Clustering will increase the availability and capacity of
your applications.
- Is the cluster correctly prepared for service applications?
You
must configure the cluster correctly before installing and starting
the first application that contains a service. Failure to configure
the cluster correctly prevents the applications from processing requests
correctly.
- Does the cluster have a backup?
You must install the application
on the backup cluster also.
Cross-cluster modules
JNDI
resources must not be shared across clusters. A cross-cluster module
requires that each cluster have different JNDI resources. A scenario
matching the following criteria will result in the log file indicating
a
NameNotFoundException:
- One module has a configured binding that generates JNDI resources.
- Another module is configured to use those generated JNDI resources.
- The modules are deployed in different clusters.
To resolve the problem, modify the module properties so that
each module uses the JNDI resources in the same cluster as it.
Stand-alone adapters
If you install an EAR
package in a network deployment environment that has dependencies
on a stand-alone adapter, ensure that the adapter can be accessed
on the deployment manager server by completing the following steps:
- Locate the BPM_Install_root/lib/ext folder
for the installed deployment manager server.
- Extract all the content contained in the stand-alone adapter RAR
package to that folder.
- Restart the deployment manager server to make the server class
loader clear the cache, and index the newly added classes and schemas.
- Install the application to the target server using the administrative
console or administrative scripts.
- 5. After you have installed the application to the target server
or cluster, remove all the content you extracted from the stand-alone
adapter RAR package into thelib/ext folder, to
avoid duplicated entry issues at run time.