A failover cluster of IOM servers. A failover
cluster is a set of redundant servers that is
configured such that, if one server fails,
another can take it's place. For the connection
factory, the failover feature is only employed at
the time a connection is made. If a connection
attempt to one server fails, another server in
the cluster is tried. If an existing connection
fails unexpectedly, there is no attempt to move
the connection to another server.