2. Take a full backup
You probably already have a backup regime in place, but before going any further, take another full backup which you can roll back should something go wrong. SBS components (Windows Server, Exchange, SharePoint) are tightly integrated so changes to one could have major effects elsewhere in the system.
Don’t forget to test the backup and verify that it will be good for a full system restore if required.
3. Complete the Exchange Server Deployment Wizard
Microsoft has developed a useful online wizard that asks questions about your Exchange Server environment, and then provides personalised instructions for your migration project. Open the Exchange Server Deployment Assistant page and select the Cloud Only option to get started.
Moving forward:
- Select Yes when asked if you have mailboxes to migrate to Exchange Online.
- Tell the wizard that your current on-premises system is running Exchange 2003.
- If you plan to replace your SBS2003 machine with a Windows 2012 Foundation Server, select the Manage users on premise
You will then be presented with an 8-step list that needs to be completed in order to migrate mailboxes to Office 365.
4. Schedule some downtime to complete the migration
Once you fully understand the migration process, you should arrange a suitable time to lock users out of the system so that you can complete the migration. It may be a good idea to extend the downtime sufficiently to complete the move from SBS2003 to Server 2012 at the same time.
You should now be in a position to complete the move to Office 365, and begin the process of completely replacing the server and its ageing software.
5. Post migration checks
Once the mailboxes have been imported into Office 365, don’t forget to complete the post-migration tasks, including assigning licenses to users (they won’t be able to access their mailboxes otherwise), adjusting your onsite DNS records to point to the Office 365 service, and updating the company MX record(s) to direct mail requests to Microsoft’s servers.
6. Safe decommissioning
With the new email system bedded in and everything working as it should, ensure that the Exchange 2003 services are disabled on your SBS machine. Because the server still contains sensitive corporate data, you will need to treat it with the same care and attention as when it was the primary email server.
After migrating all data, services and roles from the SBS server, and once you are sure that everything is running correctly on the new systems, arrange for secure deletion of the data stored on it, followed by disposal or recycling by a WEEE-certified contractor.
Don’t forget that the longer you rely on Exchange Server 2003, the greater the risk that something will go wrong, placing your company email archives in danger. As you prepare to migrate away from SBS2003, take the time to build a plan for upgrading your email too.
