It looks like Apple has released iOS 6.1.2 in an attempt to fix the calendar synchronization problem that causes Exchange servers to log a vastly increased number of database transactions and results in more transaction logs being generated, log replication within Database Availability Groups (DAGs) and potentially service disruption if disks fill up.
This problem has lasted for far too long and it follows on other issues with iOS such as calendar hijacking. In fact, dealing with a calendar seems to pose a technical challenge for Apple, possibly because their experience and focus is centered around the development of consumer applications rather than enterprise-ready software.
I don’t know if the latest fix will work or whether some new bugs are lurking and will be exposed when the fix is applied. No one knows how Apple tests their code against Exchange. If we did, we might have more confidence in the new build. Until solid proof emerges to demonstrate that it does (and that no other problem is uncovered by 6.1.2), I recommend that Exchange administrators are cautious and consider taking steps to control iOS clients. Later on, if the problem really is solved, controls like ActiveSync device access rules can be eased back to allow more user choice. If these problems have taught us one thing, it is that BYOD needs to be managed as otherwise chaos can reign.
Let’s hope that the folks in Cupertino have read the ActiveSync protocol command specification and have finally figured out how the iOS mail app should interact with Exchange. It would be nice if an iOS upgrade became something to which users looked forward with anticipation rather than trepidation. Time will tell.
Follow Tony @12Knocksinna