Migration to Microsoft Online – Cut Over Strategy

We have the opportunity to migrate just over 100 user from a local, SBS 2011 Exchange Server to a remote, cloud based, Microsoft Online exchange system. Here is what happened.


NB! 2 Weeks Preparation is needed, 15min per user to cut over (provided they dont have space or performance issues on their machines).

The process is as follows:

  1. Creation of MS Online Account – Contact us to assist with this
    1. All the mailboxes will automatically be created once you create a trust between your local server and the remote Microsoft Server
    2. Ask all of your local users to empty, clean and delete any mails they dont need – cat photos are importantant, but are they work related? maybe… most likely not!
  2. Register your MS Online Account with your local exchange server
    1. Ensure autodiscover and remote entries are working before taking any next steps
    2. Using an administrative account, allow the MS Online server to query your Active Directory, all users will be listed and you will be asked which to sync
    3. The MS Online server copies each mailbox across in the background at a rate maximum of 5gb/hr (their limitation). Your limitation is your bandwidth speed
  3. Your emails will get slow, real slow
    1. While MS Online is syncing your mailboxes you will experience delays in delivery inside and outside of your organization. Up to 30min for a mail to be sent or received 🙁 it sucks
    2. Your calendars will update slowly as well
    3. Your office network, depending on your bandwidth and number of users, will slow to a snails speed
  4. MS Online registers all mailboxes sync’d
    1. You can force a re-sync anytime, so delaying your cut-over is always an option. It will simply update the most recent mails
    2. Pick a day that suits the organization (weekends are best, else dips in work hours like lunch time or afternoon), cutting over takes 2-4hrs
      1. Changing the MX Record from your local server to your remote server
      2. Confirming your MS Online is still syncing
      3. Change all of your local users accounts to msonline account
      4. Think about setting up a shared machine for users to access webmail – https://login.microsoftonline.com/
      5. Allowing the new profile to sync – we set this to 3 months so it doesnt bomb the network. setting it to all could take hours if you have a large mailbox or slow pipe
      6. Mobile devices are easy. We simply texted each of our users the new password. They will get a popup and by typing in the new password mails sync
  5. Monitoring and Managing Expectations
    1. You are now cut over, mails are slow… this will be a few days before the users profiles sync fully and the network stabilizes
    2. Tackle teething issues immidiately, send out documentation of how to’s and links they need
    3. After say, 1 week you can address remaining issues
  6. Post Migration
    1. Take a full backup of the previous server. Ours was 500gb’s so we simply bought a drive and visualized the entire box to VHDX
    2. Export NB and Large mailboxes to PST with exchange management console. this is incase you need the data fast for priority users
    3. Finally, shutdown the old server (provided you are no longer using it for anything. If you continue using it for dhcp or dns or files there is some exchange store.exe work you need to do to stop the server from allocating resources to exchange which you no longer use)

What did we find and have to figure out?

  1. Multiple domains require a bit more thought and strategy
  2. Large mailboxes take forever
  3. DO NOT SYNC DURING OFFICE HOURS, turn it on and off after hours
  4. Think about password strategies and keep in mind, the users need to change passwords every 3 months
  5. Many hands make lite work. Train a team of people on the process and it can get done quicker. It is not rocket science