As they say, if you don’t know your destination, any path can take you there. I can apply this metaphor to Exchange Online Migration planning. For migrations from an existing on-premises exchange server environment, you can migrate all email, calendar items, tasks and contacts from user mailboxes to Office 365. The available methods are cutover, staged, and Exchange Hybrid migrations. It takes extreme caution and planning to determine which method works best in your case. These migration methods copy over all mail data, including contacts, calendar items, and tasks.
You can also use the Internet Message Access Protocol (IMAP) migration from Exchange servers, and if your Exchange server is older than Exchange 2003, IMAP migration is your only option. Note that IMAP migration will copy over only email data. And then you have migration tools that may ease out your migration efforts at a cost.
To understand this better, it is important to look at business goals for migrating to exchange. The goals can be any of the following or totally different but once identified, they could ease out your decision making in migration approach.
- Date driven goal due to hardware constraint or capacity planning.
- The total number of users required being migrated.
- Current version of exchange server
The decision-making process begins by asking whether the on-premises environment runs Exchange Server 2003 or 2007. For those environments, the next decision point is whether there are more than 2000 mailboxes. Organizations with fewer than 2000 mailboxes are supported for cutover, staged and hybrid migrations, whereas more than 2000 mailboxes are only supported for staged or hybrid migrations. However, mailbox count is not the only parameter to choose migration strategy because, given the circumstances, mailbox count greater than 300 may qualify for hybrid migration instead of a staged or cutover migration.
- Cutover migration – When the organization has less than 2000 mailboxes but want to migrate in batches, cut over migration may *not* be the right approach.
- Staged migration – You can’t use a staged migration to migrate Exchange 2010 or Exchange 2013 mailboxes to Exchange Online. So unless you use Exchange 2007, Staged Migration would *not* be the right approach.
- Hybrid migration – Hybrid migrations require some additional configuration and hardware but they allow the on-premises Exchange organization and Office 365 to function as though they are the same environment with seamless mail flow, a shared address book, and calendar free/busy federation.
- Third Party migration tools – Finally, businesses using non-Exchange email platforms can’t use the cutover, staged or hybrid options. For those businesses Microsoft provides an IMAP migration option for moving mailboxes to Office 365, or alternatively, a third party migration tool can be used.
Certainly, there is more to migration strategy than just a straightforward migration approach. Before you embark on your exchange migration journey, engage with an expert.
Office 365 Group adoption has increased over period of time and there has been considerable understanding about how and where to use Office 365 Groups. However, if you are one of those organizations that have not yet started using Office 365 Groups, I would highly recommend to start them now because
- Shared Mailbox – Unlike distribution lists, where emails resides in individual mailbox, Office 365 Groups uses shared mailbox which provides newly joined members access to history of emails and content that predates their membership. With a Distribution Group, new members only see discussions starting from when they joined
- Discoverable – Office 365 Groups are discoverable for users within your Office 365 tenant. That makes it easy for people in your organization to search for a topic name and/or description and join any related groups.
- Self Service – Users can easily create or request for access Office 365 Groups based on their permissions. Creating Distribution Groups, as well as adding and removing members, is usually done by the organization’s Exchange administrators on behalf of the users.
- Collaboration – Users have access to shared calendars, document library, OneNote notebook, etc. for collaboration needs beyond email. In case of distribution list, assorted efforts are required to form a collaborative platform.
However, with vast number of distribution groups created for disparate reasons, it was difficult for organizations to drive end-user adoption for Office 365 Groups. So Microsoft released this new functionality to transform traditional Distribution Groups to Office 365 Groups and have recently added two sets of tools to meet this request.
Exchange Admin Center
Microsoft is rolling out a change to the Exchange Admin Center to help remind Office 365 administrators about the advantages of Office 365 Groups. When administrators begin to create a new Distribution Group, they’ll be taken to the Office 365 Group creation page and encouraged to create a group there.
- Login to Exchange Admin Center and navigate to recipients -> Groups.
- Click on “Upgrade to Office 365 Groups” icon.
- On the information dialog, choose Yes to confirm the upgrade.
- If the distribution group is eligible to be migrated, then the distribution list will be converted to an Office 365 group. See the table below for distribution list eligibility for migration.
- If the distribution list isn’t eligible a dialog appears with the information that the group can’t be migrated.
- If the distribution list is eligible, but there’s a failure during migration, the distribution list won’t be changed.
PowerShell – You can also download PowerShell scripts from here to migrate the Distribution Lists to Groups in bulk.
Distribution Lists transformation to Office 365 Groups has an eligibility criteria. The following distribution lists are not eligible for Office 365 Groups Migration.
- On-premise managed distribution list.
- Nested distribution lists. Distribution list either has child groups or is a member of another group.
- Moderated distribution list.
- Distribution lists with send on behalf settings.
- Distribution lists hidden from address lists.
- Distribution lists with member RecipientTypeDetails other than UserMailbox, SharedMailbox, TeamMailbox, MailUser.
All distribution lists with member join or depart restriction as Closed will be migrated as Private.
Microsoft has not enabled any migration of Security Groups to Office 365 Groups as yet and I am sure that whenever that happens, it might end up dirty for Exchange and Active Directory Admins. Also, for customers with a hybrid infrastructure, migration will work for the Distribution Groups that are based in Office 365; but not for those based in the on-premises infrastructure. You’ll need to delete or rename the on-premises Distribution Group and create a new Office 365 Group in Office 365 using the same membership.
Office 365 Groups adoption has always faced equal criticism as appreciation. And this utility might expedite adoption and thus stream