During my routine early morning checks one day, I noticed that there there is a huge sequence mismatch between primary and standby database.Checking the alert logs revealed the below error message.
Fetching gap sequence in thread 1, gap sequence 2150-2150
Sun Mar 11 17:54:40 2012
FAL[client]: Failed to request gap sequence
GAP - thread 1 sequence 2150-2150
DBID 31666668 branch 7122030
FAL[client]: All defined FAL servers have been attempted.
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Check that the CONTROL_FILE_RECORD_KEEP_TIME initialization
parameter is defined to a value that is sufficiently large
enough to maintain adequate log switch information to resolve
archivelog gaps.
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Archived logs of a specific sequence was not available at the standby location.But was able to find this log at primary database(Thank God).
The solution was simple.Copy the specific logfile from primary to standby database.Let the standby database know about its availability.
alter database register logfile "dir+filename" ;
Recovery process would start automatically.Else stop the managed recovery and re-start it once again.
