Switching Replication Service from Site to Site
Transferring activity from one replication site to another can occur through either a controlled or uncontrolled fail-over.
- controlled fail-over—A controlled fail-over occurs when activity is transferred from one replication site to its mate replication site in a planned manner for operational reasons. By successfully following the controlled fail-over procedure, no messages will be lost, regardless of the replication mode of the messages.
- uncontrolled fail-over—An uncontrolled fail-over occurs due to a sudden loss of connectivity to a replication site with Message VPNs with a replication active state. When this occurs, only synchronous replication mode messages can be guaranteed not to be lost. Messages remaining in the replication queue will not be available at the disaster recovery site.
The following sections provide the basic steps for performing a controlled fail‑over and for recovering from an uncontrolled fail‑over: