We've completely migrated all our on-premises Exchange 2010 mailboxes to Office365 in a hybrid deployment scenario. We continue to use DirSync to keep online and on-premises AD in sync.
We are now looking to decommission all (or as much as possible) of the Exchange infrastructure as possible. I have some questions, especially in the context of the office decommissioning guidance provided here : https://technet.microsoft.com/en-us/library/dn931280(v=exchg.150).aspx (we fall in "Scenario two" for those interested).
Given the design flaw and unfortunate requirement of having to keep an Exchange 2010 server around (just for mailbox administrative tasks that cannot be performed otherwise due to source of authority constraints with on-premises AD), we have followed the recommendations and all that is left now is a single Exchange 2010 server on-premises.
- Do we need to keep this server running, or can we start it up only when we need to perform administrative tasks? It may very well stay offline for months at a time - would that be OK?
- If we do need to keep it running, can we remove the mailbox database from it?
- Do we still need to include it in backups to release deleted mailboxes and other maintenance tasks?
Many thanks,
Jaans