Exchange 2016 to Office 365 Migration

For a migration of around 80 users with the plan to decommission the on-premises server post-migration, a remote move migration might not be the most suitable option, especially if you're planning to decommission the server immediately after the migration. Remote move migration is typically used in hybrid scenarios where you maintain both on-premises and cloud-based resources.

Here are a couple of methods you could consider:

1. Cutover Migration: This method is suitable for smaller organizations and can be completed over a weekend, as you mentioned. It involves moving all mailboxes, users, and email data from an on-premises Exchange server to Office 365 and is generally straightforward. However, it requires careful planning to ensure minimal user impact.
2. Staged Migration: If you're looking to spread out the migration process over a longer period, a staged migration allows you to move batches of mailboxes to Office 365. This can help manage the load and ensure a smoother transition for users.
3. IMAP Migration: If you're only moving mailboxes and don't require calendar or contact migration, an IMAP migration could be a viable option. It's relatively simple but has limitations compared to other methods.

A version of cutover could look something like this:

• Verify that your Exchange 2016 environment is up to date.
• Ensure that all user mailboxes are on Exchange 2016.
• Configure Outlook Anywhere on your on-premises Exchange server.
• Check that you have the necessary licenses for Microsoft 365.

1. Domain Setup: Add and verify your domain in Microsoft 365. Decide on a domain type (authoritative or internal relay).
2. User Communication: Inform users about the upcoming migration and any actions they may need to take.
3. Migration Endpoint: Create a migration endpoint in Microsoft 365 to connect to your on-premises server.
4. Pilot Migration: Perform a pilot migration with a small number of users to validate the process.
5. Full Migration: Schedule and perform the cutover migration for all users. Monitor the migration process and troubleshoot any issues that arise.
6. Post-Migration: Update DNS records to point to Microsoft 365. Decommission on-premises Exchange servers if they are no longer needed. Provide support to users for any post-migration issues.
7. Final Checks: Ensure all data has been migrated successfully. Confirm that users can access their mailboxes and that mail flow is working correctly.

Regarding tooling - we use Sharegate internally for everything and it works flawlessly.