Skip to content

The iOS 6.1 Activesync Fiasco of 2013

Reports have started to materialize across the Internet that iOS 6.1 has a serious Activesync bug, causing certain calendar activity to cause redundant logging on the CAS server and quickly overwhelm storage space and CPU loads in a matter of days.

While everyone’s pointing fingers, admins are trying to save their Exchange environments from buckling under ridiculous transaction log growth and waiting with bated breath for Apple or MS to release some kind of fix. Here’s the growth on my end.



In the meantime, there are a few different strategies IT departments are using to combat the issue:

  • Warn users not to download the update – This should be the obvious first step.
  • Block EAS from iOS 6.1 devices – This is a drastic measure, and many organization wouldn’t allow that kind of disruption without some serious signing off from executives who all use iPhones. It is possible to filter the rule by iOS version if you’re using Powershell. In OWA, you can only drill down to Hardware model.
  • Fix the devices – There have been a few fixes being kicked around forums. Some are saying that simply turning off calendar sync and turning back on has solved the problem. Some are saying that a full OS wipe is required. Some are saying that you need to delete the Exchange account and add it back. Either way, we have 256 devices running iOS 6.1, so these options aren’t very elegant or feasible (but will work as a last ditch effort).
  • Put up sandbags until a fix is released – The bug affects storage and CPU. The storage (for Exchange 2010 at least) is the C:\Windows\system32\LogFiles\Exchange\W3SVC1 folder, which contains IIS logs from incoming connections. The good news is that you can delete these logs without any inclement effects. If you don’t want to delete these (for security/compliance reasons), they’re text files; I was able to compress 4.1GB down to 379MB. You can also redirect these logs to different storage temporarily. I have been seeing CPU spikes, but it hasn’t affected overall performance in any meaningful way (yet).

Hopefully, this will be a non-issue as one of the two companies releases some kind of fix. As of this writing, there hasn’t been an official communication from either company.

Post a Comment

Your email is never published nor shared. Required fields are marked *