Apple has announced that a fix for an iOS 6.1 bug that's been choking some enterprise Microsoft Exchange servers is on the way. The deceptively minor problem in Exchange calendars triggers massive activity spikes on the Exchange servers, with ballooning transaction logs and CPU utilization. The server can sometimes block iOS 6.1 users.
Yet it's only one of a range of iDevice problems that have developed since the Jan. 28 release of iOS 6.1. Almost at once, those that upgraded to the new firmware began posting to Apple and Microsoft support pages, online forums and tech blogs about fast-dropping battery life, Wi-Fi and sometimes cellular connectivity problems, and Exchange snafus.
"Apple has identified a fix [for the excessive Exchange activity problem] and will make it available in an upcoming software update," according to an Apple support post. "In the meantime, you can avoid this bug by not responding to an exception to a recurring event on your iOS device. If you do experience the symptoms described above, disable then reenable the Exchange calendar on your iOS device...."
Microsoft has posted three temporary work-arounds for afflicted enterprises, one advising 6.1 users to only view their Exchange calendars. Another is simply blocking iOS 6.1 devices from accessing Exchange. It's difficult to determine how widespread the problems are. Network World polled a half dozen enterprises and universities, with varying numbers of iPhones and iPods, and only one was reporting some "inconsistent" issues with Exchange.
"I've read about issues too, but I haven't seen anything yet," says Benjamin Levy, principal, Solutions Consulting, a Los Angeles IT services firm that specializes in deploying Apple products in businesses. "Battery life is a different story. I've heard sporadic reports and noted some shorter run times myself. And I have a consultant friend who is feeling it big time, but I haven't quantified things and mostly I solve it by having a [charging] cable in my car."
"My guess, and it's only a guess is that there may be a new sub-routine that's polling some Exchange servers a little overly [aggressively]," Levy says. "This is not something I see as a big deal, because if it's real it's limited in its impact and I would see it as likely to be addressed quickly."
For end users, the problem with Exchange seems deceptively small. According to Apple's posting, "When you respond to an exception to a recurring calendar event [meaning "to a change to a single instance of a repeating calendar event"] with a Microsoft Exchange account on a device running iOS 6.1, the device may begin to generate excessive communication with Microsoft Exchange Server. You may notice increased network activity or reduced battery life on the iOS device. This extra network activity will be shown in the logs on Exchange Server and it may lead to the server blocking the iOS device."
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