Hybrid Exchange Functionality and Post Migration

[aussupport]

Hi All,

   All the mailboxes are in O365. we have ADFS/DirSync and exchange 2010. Trying to understand keeping exchange server to do the management and smtp relay.

1. If we add new Exchange 2016 server to our domain, is that good enough? 

2. Do i have to run HCW? if so why?

3. Do i need the SSL cert?

As

[#2]

@aussupport 

Hi,

1). Adding Exchange 2016 as the management server is definitely best practice yes.  Then move arbitration and discovery mailboxes etc to Exchange 2016, configure SMTP relay, then decommission Exchange 2010 servers.

2). Running the HCW is important yes.  You could get away with running minimal Hybrid but I always run the full Hybrid as there is no real reason not to.  Running the HCW will allow you to create on-premises objects with mail attributes easily and have them synced up to O365.  This is the supported method of creating new objects in a synchronised identities methodology where on-premises AD is going to remain the Source of Authority.

3).  Yes, you will need an SSL Cert from a public SSL Cert authority.  Wildcard or SAN certs are typically used in Hybrid configurations.