You can modify the failover capability of a messaging engine during
run time. However, do not do this unless it is absolutely necessary.
About this task
To modify the failover capability of messaging engines, you change
the policy that applies to the corresponding high availability group. The
servers in the cluster receive the configuration update and the changes take
effect as soon as you save them. For example, if there is a
"One of N" policy
that has no preferred servers, and you change it to add a preferred server
and enable fail back, when you click
Save, the
HAManager ensures that the messaging
engine is running on the new preferred server; if the messaging engine is
running on a different server, the
HAManager moves
it to the preferred server.