Designing restart resynchronization procedures

Resynchronization might or might not be required when IMS is restarted and when a session is established or reestablished. This topic addresses considerations for resynchronization at IMS restart and at session restart.

If the failure occurred prior to a normal shutdown sequence between IMS and another logical unit, ensure that the session is restarted using the same half-session pairs (half-session names) that were in session at the time of failure. Further, when the session is resumed, the half-session pairs must maintain their previous relationship—that is, the former primary half session must again be primary, and the former secondary half session must be the current secondary.