I have a small network with one 2008 DC and 2 2003 DCs. I have existing Exchange 2013 SP1 on a 2012 R2 member server. I want to install a new 2012 R2 DC and demote/decommission the old 2003 DCs. This is a single site.

Everything I have read says that the Exchange 2013 SP server and 2012 R2 DC should be compatible together. Are there any gotcha's i should be concerned with when i promote the 2012 R2 server to a DC?

Hello

not need have got any issue.
after prompt new dc check exchange event log for MSExchange ADAccess

Hi,

Its ok with Exchange 2013. Please refer to below link to get more details about requirement of Exchange 2013:
https://technet.microsoft.com/en-us/library/aa996719%28v=exchg.150%29.aspx?f=255&MSPPError=-2147217396

Instead, we may be focus on decommission a domain controller:
1. Transfer FSMO role to another DC.
2. Switch GC, DNS function to another DC.
For your reference: https://technet.microsoft.com/en-us/library/cc755937%28v=ws.10%29.aspx?f=255&MSPPError=-2147217396

Thank

Hi KCorbin,

In addition to the above suggestions, you might want to increase the domain and forest fuctional levels to Win2k8 once Win2003 DCs are out of the infra.

Raise the Domain Functional Level
https://technet.microsoft.com/en-us/library/cc753104.aspx

Raise the Forest Functional Level
https://technet.microsoft.com/en-us/library/cc730985.aspx

Caution:
Do not raise the forest functional level higher if you have or will have any domain controllers running an earlier version of Windows Server.

IMP:
After you set the forest functional level to a certain value, you cannot roll back or lower the forest functional level, with the following exception: after you raise the forest functional level to Windows Server 2012, you can lower it to Windows Server 2008 R2. If Active Directory Recycle Bin has not been enabled, you can also lower the forest functional level from Windows Server 2012 back to Windows Server 2008 R2 or Windows Server 2008 or from Windows Server 2008 R2 back to Windows Server 2008. If the forest functional level is set to Windows Server 2008 R2, it cannot be rolled back, for example, to Windows Server 2003.

GO through this article before to upgrade the FFL,DFLs:

What is the Impact of Upgrading the Domain or Forest Functional Level?

Thanks to Allen and Satyajit, your posts were helpful.

I have promoted the 2012 R2 server to a DC without incident.

I had previously transferred the FMSO roles to the 2008. I may still transfer theses roles to the 2012 R2 server.

It is my plan to raise the domain and forest functional levels. I don't have a time-line to demote the existing 2003 DCs, so I will probably let them run for a week or two, then remove them and raise the functional level.

Thank you again.