Is it possible to share alternate service account Exchange server 2013 and Exchange server 2019?

Question

I'm about to move from Exchange server 2013 CU23 in a DAG configuration to Exchange server 2019 CU8 also in a DAG configuration. When we moved from Exchange serve 2010 to 2013 we needed to create a new ASA account, but I cannot find any information about if that's necessary now as well or if it's possible to use the same. I get som hints about sharing the ASA between Exchange 2016 and 2019, but nothing so far about Exchange 2013 and 2019. Anybody know? Or maybe have this experience and ca share it with me? I would be very grateful. Micke

Answer 1

Yes, as long as the same namespace is used, you can do that

All Client Access servers that share the same namespaces and URLs need to use the same alternate service account credentials. In general, it's sufficient to have a single account for a forest for each version of Exchange. alternate service account credential or ASA credential

https://learn.microsoft.com/en-us/exchange/configuring-kerberos-authentication-for-load-balanced-client-access-servers-exchange-2013-help?redirectedfrom=MSDN

https://techcommunity.microsoft.com/t5/exchange-team-blog/exchange-2016-coexistence-with-kerberos-authentication/ba-p/603955

applies to 2013/2016/19 as well

The reason you cant do that in 2010 was the CAS Array issues and the requirement for sep name spaces.

Answer 2

Thanx you for the fast reply,

Regards

Micke