Exchange Sever Install In Existing AD Environment with Exchange Online Mailboxes

Question

I am working with a client that wants to soft/hard match existing on prem/cloud accounts. The cloud accounts already have Exchange online mailboxes and the users are currently using 2 distinct identities, one for cloud and another for on prem. I am recommending that they install an Exchange 2019 server and extend the schema and stay in a supported hybrid state. Can someone please verify that I am on the right path with the steps described below:

Confirm replication is in a healthy state
Extend the AD schema
Install Exchange 2019 and select management tools when prompted
Run the HCW to license the server and back out of the rest of the installation process
Run IDfix and remediate any issues
Ensure that the ProxyAddresses attribute is populated with the proper SMTP addresses
Install AD Connect and begin synching

Will I be able to use the EAC GUI after I install the Exchange Tools?

I am a bit concerned because I see posts indicating that you need to create on prem mail contacts but I wouldnt think that would be necessary when you are matching the on prem accounts with cloud accounts. I am also unsure of how to license the server but I am thinking that the HCW install is the way to go. Can anyone provide some further insight into this process?

Answer 1

You are true that when connecting on-premises accounts with cloud accounts, you do not need to build on-premises mail contacts. Users who don't have a corresponding AD account are represented via mail contacts. In your situation, all users already have AD accounts. Hence I don't believe mail contacts are necessary.

The best method for licensing the Exchange server is through the HCW. The appropriate licenses for your environment will be chosen automatically.