We are currently in the planning stages of migrating a client's Exchange 2007 database to Office 365 Exchange online. The part of the project that we're not sure about is how to only move one database and leave the other in production.
The situation is such that we have two organizations sharing one Exchange server. Both have their own Exchange db, but share a single local domain. Each does have it's own www domain, so separating them isn't an issue.
All of the documentation we've found so far assumes that only one organization is being migrated and then the on-premises Exchange server will be decommissioned. In our case, we have two organizations, one will continue using the on-premises Exchange server while the other will migrate to Office 365 Exchange Online.
Has anyone had any experience with this or can someone point us in the right direction?