Getting ready to apply CU9 to our Exchange 2013 CU7 box. I ran across an installation note that thought I should check out. The article is at http://www.howto-outlook.com/news/exchange2013cu9.htm. It mentions:

Important!
When installing Exchange 2013 CU9, make sure you also explicitly execute:
setup.exe /PrepareAD /IAcceptExchangeServerLicenseTerms
This command is being skipped since CU9 doesnt contain any schema changes when compared to CU7 and CU8. However, CU9 does include RBAC changes which are otherwise not applied and the improvements in KB3050877 will not work.

I didn't see this in the Microsoft kb article. Is this a preferred setup o

You should run /PrepareAD explicitly with CU9 so you get the new cmdlets. This step is run automatically when you run setup, expect in cases where the schema is not updated, hence the requirement. I always run each prep command separately as a rule. In a multi-domain forest, that's the recommended path.

In a single domain AD forest, its not required to run each prep command separately, except in this case where there is an exception to the rule

http://blogs.technet.com/b/exchange/archive/2015/06/16/released-june-2015-exchange-cumulative-update-and-update-rollups.aspx

 Note: If you do not see the new CMDlet parameters available in Exchange 2013 CU9, please perform /PrepareAD manually.   

Thanks much for the advice and help!