Checking for Alwayson manual sync process for redo queue data
Hi, I have seen frequently few databases are having synchronization issue with secondaries and monitored the same and found redo data queue size is around in 2MB in secondary replicas. I have tried in GUI for resume data and do syncup but it's failed giving error. Do we have any code for apply Redo pending data on secondary replica databases manually.
This is the command to resume availability group replication for an individual database: ALTER DATABASE [database_name] SET HADR RESUME; Once this is set, there is not a separate command to actually force the replicated transactions through the redo queue. The redo rate is limited by system capacity and, as noted in the comments, the redo queue may only get one thread per database (1 thread per 4 CPUs on systems with more than 5 CPUs - [
https://msdn.microsoft.com/en-us/library/ms187465.aspx]) so an identically sized secondary can still fall behind a busy multi-threaded workload on a primary. It's possible that 2mb is just your high-water mark in this catch-up process. :