No mailbox sync in a long time, A5/6 not clearing
I've been observing this issue for a while now and need to take action. Our EV setup handles two Exchange farms, a 2007 farm and a 2010 farm. EV is version 10.0.3 RU2, on a 2008R2 with 16 CPUs and 32GB RAM. There are separate archiving task for each of the four mailbox servers and each of the two journal mailboxes.
Everything is fine on 2010, but we've been processing through a large backlog on 2007, due to recently having added a lot of users to archiving. I haven't seen a mailbox synchronisation on the 2007 server in a long time, the status monitor is showing a 41447 for the server, and if I look in the event log, I see the 3197 events for all the other mailbox servers and the journals, but not this server. There are no error messages in the event log pertaining to the 2007 archiving task.
Another thing that I noticed, is that the A5 and A6 queues for the 2007 mailbox server haven't cleared in a long time. They are processing, albeit slowly, but keep filling back up before they hit 0. I understand that A5 is the mailboxes that need to be processed, and A6 is moved items inside a mailbox. I've once been given to understand that all other queues have to clear for A7 to process, can someone confirm that?
Task schedule (since this question always comes up): at the moment, I am running the archiving task at all times, to try and deal with the backlog. There is a 1 hour break in the schedule to allow for the synchronisation. I previously had the archiving suspended during business hours, but that didn't seem to make a difference.
Long story short, I need this sync to happen because we recently changed a few policies. What can I look at, what can be changed or improved?
Your advice is greatly appreciated.