In TN#1429885 or knowledge center:
There are statements:
“Ensuring that the UIDVALIDITY value is different for replicas on different server will force the IMAP-compliant clients to discard and re-fetch the cached data for messages in these folders, ensuring that the IMAP client is synchronized with the replica being accessed after a failover. ”
So when failover happens, when a IMAP access switch from server A to server B to a different replica, all mails will be downloaded again. This will bring big disk IO pressure to serverB.
In fact, in customer environment, we see high diskIO wait and CPU usage after failover.
So customer would like to prevent IMAP from re-fetching data after failover?
BTW, SPR JBGMACHCKN was created before.