Decommissioning your Exchange 2010 servers in a Hybrid Deployment

I wanted to advertise this blog post by Timothy Heeney on the Exchange Team blog, Decommissioning your Exchange 2010 servers in a Hybrid Deployment, since Forefront Online Protection for Exchange (FOPE), the product I write about (FOPE User Guide), is in the mix on hybrid deployments and hybrid is a logical next step for many FOPE customers. (A hybrid deployment means you host a portion of your mailboxes on premises and a portion in the cloud.) Specifically, the post walks through the decisions to think through as you decide to decommission on-premises servers after moving mailboxes to the cloud.

Many organizations have chosen to configure a hybrid deployment with Exchange Online to take advantage of different features such as rich mailbox moves and cross-premises calendar free/busy sharing. This includes Exchange 2003, Exchange 2007 and Exchange 2010 organizations that require a long-term hybrid configuration with Exchange Online and organizations that are using a hybrid deployment as a stepping stone to migrating fully to Exchange Online. So, at what point should these organizations decide to get rid of their on-premises Exchange servers used for the hybrid deployment? What if they have moved all of the on-premises mailboxes to Exchange Online? Is there a benefit to keeping on-premises Exchange servers? While it may seem like a no-brainer, the decision to get rid of the on-premises Exchange servers is not simple and definitely not trivial.