Adding fail-over hosts
You can add secondary LDAP servers to your configuration for fail-over purposes. The implementation checks each call to the LDAP server (that fails) and looks for some specific exceptions/errors. When one of the known errors is seen, it is interpreted as a failed server and the session provider switches to the next server in the list. The switch is done in a round-robin fashion, and the state is not saved between restarts of the session provider. Therefore, you must make sure to keep the primary server first in the list.
Note that if a fail-over occurs during an attempted logon, that logon will fail. The new server will be used by the next logon attempt. When a switch happens, an INFO message similar to the following is logged in the SessionProvider log:
2013-03-04 08:12:38,525 INFO SessionProvider SessionProvider: Switching server from
server1.company.com to server2.company.com
To enter fail-over hosts , use the property ldap.hostName.failOver.conf#. See Description of configuration properties.