Exchange Server Storage Changes
Microsoft revealed some interesting new changes for both Exchange Server 2013 and the upcoming Exchange Server 2016 release when it comes to storage at the Microsoft Ignite Conference. The biggest of these announcements is probably support for ReFS (Resilient File System) for data volumes. Microsoft's newest recommendation for Exchange Server 2016 is to use ReFS with BitLocker enabled on all data volumes (ReFS cannot be used for the C drive as Windows does not support booting from ReFS). The logic behind this new storage recommendation is that ReFS is more resilient against logical corruption than NTFS, provides better availability than NTFS, is more scalable with large data sets, and that it continues to support BitLocker. BitLocker is also recommended for all Exchange Server 2013/2016 drives as part of the latest update to the Preferred Architecture.
The second major announcement impacts both Exchange Server 2013 and Exchange Server 2016 - both versions now support dynamically sized VHDX files when Exchange is installed on Hyper-V. Previously when Exchange was virtualized it required fixed sized VHDs or VHDXs, but Microsoft has now certified that dynamically sized VHDX files don't impact IOPS enough to bar their use. Microsoft is still recommending the use of physical Exchange servers using JBOD storage in order to provide affordable Exchange storage with minimal complexity, but if you must deploy Exchange Server 2013 on Hyper-V the job just became a bit easier.