1. Tips and Tricks for
Migrating to Exchange
Online
Steve Goodman
12th February 2014
2. Who am I?
• Dad and Husband
• Infrastructure Consultant at Ciber UK
• Exchange VTSP at Microsoft
• Exchange Server MVP
• Host of The UC Architects Podcast
• Blogger, PowerShell Scripter, Author
3. What am I talking about this evening?
• What to think about before you think about migrating
email
• Options for migrating email to Office 365
• Top tips for each method of migration
5. What to consider before you set things up
• Is your Active Directory structure an easy fit
for Office 365?
• Are you prepared (or able) to update User
details?
• Do you have an understanding of your
Exchange environment and patch levels?
6. What to consider before you set things up
• Do you know what clients and apps are in
use, and can you update them?
• What resource do you have available to
support your migration?
• What are your deadlines to migrate?
8. Cutover Migration
• Migrates ALL mailboxes in one go
• Suitable for Exchange 2003, 2007, 2010 and
2013
• Limited to a maximum of 2000 mailboxes
• Uses Outlook Anywhere to copy mailboxes
9. Staged Migrations
• Migrates mailboxes in batches
• Suitable for Exchange 2003 and 2007
• Uses Outlook Anywhere to copy mailboxes
10. What is a Hybrid Migration?
• Link Exchange to Exchange Online
• Requires Exchange 2010 or 2013
• Move mailboxes, not copy them - highest
fidelity of moves
• Move to or from the Cloud
11. Other Migration Methods?
• IMAP Migration
• Wide range of source systems, low fidelity
• PST Migration
• Export as PST, Import using PST Capture Tool, flexible but
crude
• Third-Party Tools fill the gaps
• Cloud-based tools (e.g. BitTitan MigrationWiz)
• On-Premise tools (Quest, BinaryTree)
13. Cutover and Staged Migration Tips
• Make sure Outlook Anywhere is enabled, available externally
and you have a valid third party certificate
• Test using the Remote Connectivity Analyser
• The Mailbox is copied so needs profile reconfiguration
• Can involve visiting desktops
• Do you have mailboxes hidden from the GAL?
• Ensure mailboxes you are migrating are visible.
14. Cutover and Staged Migration Tips
• Mailbox permissions aren’t copied and need to be re-applied
• New Collect-MailboxPermissions.ps1 on it’s way to www.stevieg.org
• After migration is completed switch off Internal AutoDiscover
• Set-ClientAccessServer <ServerName> -AutoDiscoverInternalURI:$null
15. Cutover Migration Tips
• Get Active Directory and DirSync ready for after your migration
• You can sync user details and passwords as you cutover
• If you use DirSync think about how you’ll manage Exchange
• Are you leaving DirSync in place?
• Lower DNS TTLs to enable a quick switchover
16. Staged Migration Tips
• Perform adequate testing before moving real users
• Failed migrations can leave users in a half-migrated state
• Move People and Shared Mailboxes together where you can
• If you struggle to do this, a Staged Migration might not be for you
• Convert Mailboxes to MailUsers after each migration batch
• http://community.office365.com/en-us/wikis/exchange/845.aspx
17. Hybrid Migration Tips
• Make sure Exchange is published to the Internet optimally
• Correct Certs, AutoDiscover, No Pre-Auth for Hybrid-related URL Paths
• Exchange 2010 includes all you need for a hybrid migration
• You don’t need a “Hybrid Server”, but you do need a minimum of SP3
• Exchange 2013 is the best choice for a long coexistence
• Easier setup, free hybrid license and target for new Hybrid features
18. Hybrid Migration Tips
• Clean up any cross-forest sidHistory issues before migrating
• sidHistory isn’t migrated and can break permissions
• If you can, remove Public Folders rather than migrate them
• No compelling co-existence story and added hassle
• Use “Suspend When Ready to Complete” to perform quick
switches of mailboxes
• Performs a full sync of mailboxes, allowing you to perform a final sync
then switch in minutes
19. Tips for any migration method
• Export oversize messages first
• Export messages over 34MB to PST and / or encourage users to clean
up mailboxes
• Third Party tools can make complex migrations easy
• Cloud-based tools like MigrationWiz save a lot of time and can provide
flexibility Microsoft tools cannot
• Think about the user experience
• A simple server-side setup might mean a complex desk-side migration
21. Summary
• Understanding your environment before you begin is critical to
success
• Microsoft provide Cutover, Staged, Hybrid and IMAP migration
methods
• Additional options include PST and 3rd party tools
• Hybrid migrations require a little more setup, but are worth the
effort