I have asked that question of the product team and not received a response.
(Initially I just asked “is the service affected?” and got the response “no”. After years of talking to those folks I’ve learned to ask the direct question first and go for details later…) I will say that on the patchmanagement list, one gentleman who was running the iOS beta wrote that there was “sometimes” a problem with O365, but it could usually be fixed by resending the message a few minutes later. Which sounds to me like multiple web farms not configured the same way. But I have no concrete data to support my guess. From: listsad...@lists.myitforum.com [mailto:listsad...@lists.myitforum.com] On Behalf Of Senter, John Sent: Tuesday, September 19, 2017 8:40 AM To: exchange@lists.myitforum.com Subject: RE: [Exchange] RE: iOS 11 is scheduled for release tomorrow... How is O365 not affected by this? Are they not running server 2016 or did they step the cipher down to HTTP/1.1? We were putting our Exch 2016 servers in production tonight, but are holding off for a week because we did not feel comfortable doing the OS reg hack the same day the servers were going in. Like to test even the simplest changes before going live. From: listsad...@lists.myitforum.com<mailto:listsad...@lists.myitforum.com> [mailto:listsad...@lists.myitforum.com] On Behalf Of Michael B. Smith Sent: Monday, September 18, 2017 4:22 PM To: exchange@lists.myitforum.com<mailto:exchange@lists.myitforum.com> Subject: RE: [Exchange] RE: iOS 11 is scheduled for release tomorrow... Item 1 - no Item 2 and 3 - yes From: listsad...@lists.myitforum.com<mailto:listsad...@lists.myitforum.com> [mailto:listsad...@lists.myitforum.com] On Behalf Of Brett Whatley Sent: Monday, September 18, 2017 3:57 PM To: 'exchange@lists.myitforum.com' Subject: Re: [Exchange] RE: iOS 11 is scheduled for release tomorrow... Is 365 affected? Sent from my BlackBerry — the most secure mobile device — via the Rogers Network For Remote Support Click Here<http://www.ineedpc.help/> [cid:image001.jpg@01D33124.8CBFCC80] [cid:image002.jpg@01D33124.8CBFCC80] Brett Whatley Solve-IT.ca a division of Ozymandias Creations, Inc. 379 Ridge Rd West Grimsby, ON L3M 4E7 Phone: 905-388-2597 x.121 Mobile: +1 9053795695 E-mail: br...@solve-it.ca<mailto:br...@solve-it.ca> [cid:image003.jpg@01D33124.8CBFCC80] [cid:image004.jpg@01D33124.8CBFCC80] [cid:image005.jpg@01D33124.8CBFCC80] ♲ Please consider the environment before printing this e-mail This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error, please notify Solve-IT.ca. This message contains confidential information and is intended only for the individual named. If you are not the named addressee, you should not disseminate, distribute or copy this email. Please notify the sender immediately by email if you have received this email by mistake and delete this email from your system. If you are not the intended recipient, you are notified that disclosing, copying, distributing or taking any action in reliance on the contents of this information is strictly prohibited. From: mich...@smithcons.com<mailto:mich...@smithcons.com> Sent: September 18, 2017 3:56 PM To: exchange@lists.myitforum.com<mailto:exchange@lists.myitforum.com> Reply to: exchange@lists.myitforum.com<mailto:exchange@lists.myitforum.com> Subject: [Exchange] RE: iOS 11 is scheduled for release tomorrow... Yes, it’ll jack up wherever the external connection is. Since 2016 proxies to 2010 in your case, the 2016’s are acting as CAS frontends and will cause the problem. From: listsad...@lists.myitforum.com<mailto:listsad...@lists.myitforum.com> [mailto:listsad...@lists.myitforum.com] On Behalf Of Senter, John Sent: Monday, September 18, 2017 3:39 PM To: exchange@lists.myitforum.com<mailto:exchange@lists.myitforum.com> Subject: [Exchange] RE: iOS 11 is scheduled for release tomorrow... Will this only affect mailboxes on Exch 2016 or will it also affect users that are on Exch 2010 with 2016 in front? We are about to place 2016 in front of 2010 to start the migration process and need to know if that is going to jack up the users still on Exch 2010. From: listsad...@lists.myitforum.com<mailto:listsad...@lists.myitforum.com> [mailto:listsad...@lists.myitforum.com] On Behalf Of Michael B. Smith Sent: Monday, September 18, 2017 3:07 PM Subject: [Exchange] RE: iOS 11 is scheduled for release tomorrow... Further information on [1], as Microsoft and Apple release additional details. [1] This only occurs when Exchange Server 2016 is installed on Windows Server 2016. It actually will impact any web app on Windows Server 2016 to which an iOS 11 device attempts to connect. The issue occurs because iOS 11 improperly negotiates a HTTP/2 TLS connection, and HTTP/2 is the default on Windows Server 2016 and iOS 11. While this is not an Exchange issue per se, Exchange is the application most likely to be affected. Microsoft offers a workaround, described in this article, by disabling HTTP/2 thus forcing a fallback to HTTP/1.1: https://support.microsoft.com/en-us/help/4032720/how-to-deploy-custom-cipher-suite-ordering-in-windows-server-2016 (If you find the article title to be irrelevant – well, so do I.) And a new item: [3] Yammer and Dynamics CRM apps have not yet been updated for iOS 11. There are a wide variety of Intune changes/impacts with iOS 11: https://blogs.technet.microsoft.com/intunesupport/2017/09/12/support-tip-intune-support-for-ios-11/ Perhaps the two things most notable to your users: [3a] An updated Company Portal and Managed Browser are required for iOS 11, and [3b] Drag-and-drop (a new feature of iOS 11) is disabled when a device is enrolled with Intune. From: Michael B. Smith Sent: Monday, September 18, 2017 2:22 PM Subject: iOS 11 is scheduled for release tomorrow... And that may not be a good thing in all cases… Known issues to be aware of: [1] Exchange ActiveSync is broken under certain configurations. Apple is aware of the issue and pursuing a fix. [2] The default picture format for iPhones 7/8/X is changing. As a Microsoft employee wrote earlier today: The new photo and video formats result in files about 1/2 size of the old JPEG and video formats, while having better quality. The problem is that new files will likely not open properly outside of your phone until everything that you use to work with photos updates to work with new HEIF formats. To check if your iOS 11 phone uses the new format, go to Settings > Camera > Formats. "High Efficiency" is new and "Most Compatible" is the old / current. I do not suggest to just turn this off; hey - getting files half the size is super cool. Just realize that if you use the photos outside of your phone that there might be temporary issues with viewing. Windows and OneDrive do not yet support the new formats. h/t ninob You may wish to suggest to your user communities that they delay upgrades because of the EAS issue.