Exchange 2013 CU11 has been released to the Microsoft download centre! Exchange 2013 has a different servicing strategy than Exchange 2007/2010 and utilises Cumulative Updates (CUs) rather than the Rollup Updates (RU/UR) which were used previously. CUs are a complete installation of Exchange 2013 and can be used to install a fresh server or to update a previously installed one. Exchange 2013 SP1 was in effect CU4, and CU11 is the seventh post SP1 release.
This is build 15.00.1156.006 of Exchange 2013 and the update is helpfully named Exchange2013-x64-cu11.exe. Which is a great improvement over the initial CUs that all had the same file name! Details for the release are contained in 3099522.
Whether or not your AD Schema needs to be updated depends upon your initial Exchange 2013 version. This will dictate if the AD Schema needs to be modified. Check the values as noted in this post. CU11 does not contain additional AD Schema changes, but may contain additional RBAC definitions.
Updates Of Particular Note
Cumulative Update 11 includes a change in behaviour when Exchange Server 2013 coexists with Exchange Server 2010 or 2016. These changes are outlined in the following blog article: Exchange Management Shell and Mailbox Anchoring.
This update also includes new daylight saving time (DST) updates for Exchange Server 2013. For more information about DST, go to Daylight Saving Time Help and Support Center.
Some Items For Consideration
As with previous CUs, CU11 follows the new servicing paradigm which was previously discussed on the blog. The CU11 package can be used to perform a new installation, or to upgrade an existing Exchange Server 2013 installation to CU11. You do not need to install Cumulative Update 1 or 2 for Exchange Server 2013 when you are installing CU11. Cumulative Updates are well, cumulative. What else can I say…
After you install this cumulative update package, you cannot uninstall the cumulative update package to revert to an earlier version of Exchange 2013. If you uninstall this cumulative update package, Exchange 2013 is removed from the server.
Ensure that you consult with all 3rd party vendors which exist as part of your messaging environment. This includes archive, mobility and management services.
Ensure that you do not forget to install this update on management servers, jump servers/workstations and application servers where the management tools were installed for an application. FIM and 3rd party user provisioning solutions are examples of the latter.
Disable file system antivirus prior to installing.
Once server has been restarted, re-enable file system antivirus.
Note that customised configuration files are overwritten on installation. Make sure you have any changes fully documented!
CU11 may contain AD Schema updates for your organisation – please test and plan accordingly! Whether or not your AD Schema needs to be updated depends upon your initial Exchange 2013 version. This will dictate if the AD Schema needs to be modified. Check the values as noted in this post.
Please enjoy the update responsibly!
What do I mean by that? Well, you need to ensure that you are fully informed about the caveats with the CU and are aware of all of the changes that it will make within your environment. Additionally you will need to test the CU your lab which is representative of your production environment.