I have some issues with one of my Exchange2013-servers and want to upgrade from CU4 to CU8 to see if this will correct the issues. 2 questions:

• Where can I find step-by-step documentation on how to perform the upgrade, including the necessary steps to prepare AD?
• I have found articles saying that any customizations on the servers will be lost, what kind of customizations could this be? I hope that all setup with connectors, URLs and so on is preserved during the upgrade?

The server with the issues is member of a DAG.

BR,

Thor

Hello

its not a difficult.
if use gui start install in cas server. need schema and domain admin permission to upgrade schema and AD.
and if finished without error set mailbox to maintenance mode and start update server, and if not error start maintenance on another mbx node and upgrade...

Any customized per-server settings you make in Exchange XML application configuration files, for example, web.config files on Client Access servers or the EdgeTransport.exe.config file on Mailbox servers, will be overwritten when you install an Exchange Cumulative Update (CU). Make sure that you save this information so you can easily re-configure your server after the install. You must re-configure these settings after you install an Exchange CU.

Hi and thanks for your answer,

The server with the problem is a MBX-server and I would like to upgrade only this server first. Is it supported to run DAG-members with different CU-versions?

Hello

http://blogs.technet.com/b/exchange/archive/2013/02/08/servicing-exchange-2013.aspx

Q: In a Database Availability Group configuration do all servers need to be at the same CU revision?

A: Customers should plan their deployments such that all servers in a Database Availability Group are running the same CU revision for the version of the product they are using. During a CU upgrade, it is supported for individual servers in the Database Availability Group to be deployed with different CU versions. This is expected to be a temporary condition until all servers have been upgraded.

Q: Do all servers in a Client Access Array need to be at the same CU revision?

A: Similar to Database Availability Groups, co-existence of multiple CU revisions in a single array is supported during the upgrade process.

I use this article from exchangeserverpro.com, it does a good job of explaining all of the requirements and steps for applying a CU to Exchange 2013.

Hi,

Thank you for your answer, this is a really good article.

It says "Have documented any customizations such as OWA, config files on servers, registry changes, Lync integration, or third party add-ons", do you know what I should check/document regarding OWA?

Hello,

Generally, applying CU will not affect OWA settings. Have you configured any redirection or customization on OWA?

Thanks,

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