Learn about the paths to migrate supported versions of Exchange to Exchange 2016, along with three ways to migrate older, unsupported versions.
- [Instructor] One of the most common reasons for creating a coexistence environment is to migrate from one version of Exchange to another. Like many server products, moving to a newer version of Exchange is not done by upgrading the installation on the existing servers. Instead, new servers are brought online, and the various services and data stores are migrated from the old version to the new. That's where the coexistence environment comes into play. It's also where some limitations come into play, particularly the versions that are supported for coexistence.
An active directory forest with Exchange 2010 and Exchange 2013 objects will allow the installation of an Exchange 2016 server. This support for the two previous versions is common, in fact it's persisted for quite a while. If you're migrating from an Exchange 2010 or Exchange 2013 environment to Exchange 2016, the migration path is pretty straightforward. The active directory preparation for Exchange 2016 is completed, Exchange server 2016 is installed, and you start moving mailboxes.
If your active directory forest contains Exchange objects older than Exchange 2010, things get a little trickier. Exchange 2016 won't allow itself to be installed into an Exchange organization that has older Exchange objects. If you have an Exchange 2007, or Exchange 2003 server, your migration to version 2016 will require extra steps. Technically, it's possible to create an entirely new active directory forest and install your Exchange 2016 servers in that environment.
This works because an Exchange organization is entirely contained within a forest. If you create a new forest, the older versions of Exchange won't be noticed. You would then need to create a forest trust before you can begin migrating data from the older servers to the new ones. This is uncommon and not the preferred method of migrating from older versions, because it requires you to create a whole new infrastructure of hardware, networking, server licenses and DNS name spaces.
These separate environments must be maintained throughout the coexistence. Then, once the migration is completed, you have to decide what to do with the leftover forest, one with a name space that you've probably used for over a decade. The more common way to migrate from older versions of Exchange is by performing two migrations. It's been the norm that each version of Exchange server supports coexisting with the previous two versions.
Just as Exchange 2016 supports 2013 and 2010, Exchange 2010 can coexist with Exchange 2007 and 2003. You can migrate an Exchange organization as old as Exchange 2003 to 2010 and once that migration is complete and the old servers have been decommissioned, you can begin the migration from Exchange 2010 to 2016. As of this writing, Exchange 2010 and Exchange 2013 are still available to purchase from the Microsoft store and from other vendors.
The downside to this migration path is the time it will take to complete two migrations, and it may include the cost of an in-between version of Exchange that you didn't intend to keep. But the advantage that often outweighs those costs is the savings of not having to buy a whole new infrastructure and the convenience of being able to continue with the domain names and other resources that you already use. There is one other option that may be available to you. There are third-party tools designed to facilitate migration from older versions of Exchange that can't coexist.
Don't misunderstand, they don't overcome the barrier of having Exchange 2003 and Exchange 2016 installed in the same organization, but they do provide you a different option. Some do it by creating an export of all configuration and data, or by migrating across different forests and then migrating back to a new environment. And some offer this service as no charge as part of purchasing a subscription to their hosted Exchange solution, or similar product.
But these are your three options for migrating from Exchange organizations older than 2010. As we move forward in this course, we're going to take a look at the specific steps involved in migrating from 2010 or 2013 directly to Exchange 2016.
- Preparing for hybrid configuration
- Deploying a hybrid configuration
- Troubleshooting Exchange Online
- Troubleshooting Office 365 clients
- Configuring the gateway
- Managing sharing policies
- Troubleshooting cross-forest availability
- Troubleshooting mail flow
- Migrating from earlier versions