Now that we’ve established how to get users up into the cloud when implementing Office 365, it’s time to discuss your migration options when it comes to Office 365.
If you’re moving to Office 365, it’s likely that you wish to take advantage of features such as Exchange Online or SharePoint Online in order to replace on-premise solutions. For this post, we’ll focus mostly on moving Exchange to Exchange Online since that is the most common migration.
Your first option is both simple and complex, the Hybrid Migration, and requires a certain version of the to which product you’re migrating. For Exchange purposes, this means Exchange 2010 SP3 or higher needs to be present in one form or another.
It’s possible to migrate Exchange 2007 SP3 this way, but you have to have 2010 to act as a migration endpoint. In this scenario, your on-premise implementation is connected up to your Office 365 tenant directly and they exist much as if they were in the same on-premise server farm. Users homed on premise are directed to the on-premise servers and vice versa.
The advantages here are that you can have users extant in both environments for a time and can perform testing and vetting while your two environments live in zen-like coexistence. When you’re ready to pull the plug, simply move all users and data to the online tenant and decommission the on-premise environment.
Next up is the quick and brutal cutover migration. Much like the Hybrid migration, you connect your on-prem data to the online tenant, but in this case you move all data and users in one fell swoop.
Move everything, cut over DNS, prop your feet up and enjoy a cold glass of cloud infrastructure.
The advantages are, of course, less time and infrastructure dedicated to the transition. The negatives are an inability to test effectively and an increased chance of user disruption.
How do you choose?
Cutover migrations can move up to 2000 Exchange 2010 or 2013 mailboxes. Anything over that and you should use a hybrid deployment for 2010 or 2013. Cutover Migration for Exchange uses Outlook Anywhere, so it does not require Dirsync whereas Hybrid and our next migration type do.
Staged Migrations are essentially the combination of the previous two. They aren’t for long-term, happy coexistence between environments, but move users and data in batches rather than the single large move found in cutover migrations.
Through a combination of PowerShell and management console work, the user mailboxes are synced with their cloud counterparts. This is ideal for Exchange 2003 and 2007 if you have implemented Dirsync. Otherwise, it’s cutover for you.
The final option I’ll discuss is third party tools. There are plenty out there that can assist in performing a migration. One of our favorites is a tool called Skykick that can migrate almost any mail system to Office 365 and automates a lot of the heavy lifting.
These tools exist for Exchange, SharePoint, and even for files services in some cases and they continue to get better as Office 365 evolves.