75 ways to demystify DB2: #2: Tech Tip: Why infinite logging is not supported in HADR configuration ?
subra_murali@ibm 2000000GHY Visits (7955)
Hello DB2 DBAs
Hope you all had a relaxing happy Holiday Season! I wish you a Productive 2015!!
Recently we had a questions asked about the feature to use infinite logging in a HADR setup. The concern is the significant rollback time when there is a need to failover. There is no limit on the size of inflight transaction with infinite logging. so the time it requires to back out inflight transactions (required as part of takeover processing) would be very large. Then the database is not really highly available.
Another concern is not having enough disk space in the active log path of standby database necessitated by the Infinite logging option. We believe business value of employing the HADR feature would be significantly limited, if fail over time is very significant. So this option will not be supported in HADR configuration.
Hope you find it useful!! As always reach out to us if you have any questions or comments. It is highly appreciated.
DB2 LUW Technical Support