Remove On Premises exchange Hybrid and go fully Online

Carol Chisholm We are an IT service provider and have moved a number of clients to Office 365 over the years. Most have been through methods other than a Hybrid Deployment (cut-over, staged, PST import, 3rd party tools, etc.); however, some have been via Hybrid Deployment. I was directly involved (years ago) with the migration (using a Hybrid Deployment) for two clients, one with 17 mailboxes and one with 122 mailboxes. In both scenarios we left an Exchange Server in the environment.

While I'm no longer involved with management of the mail environment for these customers, when I saw this conversation heat back up I asked our Director of Services during a call this morning if we still have the Exchange Servers in these customer environments, and if so, what do we use them for? He said we do still have them in the environment; however, he couldn't think of a single task we perform on the Exchange Server for day-to-day management. He said everything is done in either AD (with some attribute editing required) or Office 365. I asked if we did anything on the Exchange Servers when a employee is hired/terminated, and he said "no".

While it may just be my mind playing tricks on me (or old age), years ago I recall Microsoft somewhat promoting a Hybrid Deployment as a preferred migration method. Additionally, I seem to recall articles using terminology such as "Hybrid Migration" not "Hybrid Deployment". It seems "Hybrid" has been positioned as more of a state than means to an end. Or stated another way, there may never be a Microsoft provided solution for decommissioning all on-prem Exchange Servers once in a Hybrid Deployment. This may be because Microsoft doesn't view a Hybrid Deployment as many often do; as a way to easily move to Office 365 and get rid of on-prem Exchange.