Forum Discussion
Mark Dobrzynski
Nov 07, 2016Copper Contributor
Migrating On-Prem Distribution Groups to Exchange Online in Hybrid Mode
I have come across a number of articles on migrating distribution groups to Office 365 when you're not in hybrid mode. My situation is having hundreds of DLs on my on-prem Exchange environment that I...
TonyRedmond
Nov 14, 2016MVP
To make sure that I understand what you want to do: you have a set of DLs on-premises and you now want to move them to Exchange Online without changing any of the members. You don't want to create new Office 365 Groups based on the DLs - you just want to use the DLs as they are.
Do you have a hybrid environment? If so, you can use AADConnect to synchronize the on-premises DLs with AAD so that they appear in the cloud GAL. The groups will have to be managed on-premises because they are "owned" by that environment.
If you don't want to synchronize the groups, you can recreate the DLs in the cloud. This is a manual process as there is no tool that I know of to move a DL from one environment to the other. However, it's easy enough to use PowerShell to export DL membership to something like a CSV file (on-premises) and then read that CSV file to create the DL in the cloud.
- Christian BruyereAug 16, 2018Copper Contributor
Hello TonyRedmond,
Sorry, your answer is quite old now but I have a question regarding the situation.
I'm in a similar situation with the customer here:
- Made a hybrid deployment to migrate from Exchange 2010 to Office 365;
- Have AAD Connect (and ADFS)
- Migrated almost all users (and shared mailboxes, etc.)
- The end goal is to shut down the Ex10 server since I've told uninstalling it is a terrible idea. We'll be managing things like SMTP Addresses from the AD Attribute Editor.
Now about the DGs: We've sync'ed them all with AADC. We can see them in o365 AC and ExO but not manage them as expected.
If I would like to manage them there, can I simply remove the DG OU from AADC Sync?
EDIT: Thinking about it, I've realized doing what I've described above should change the ID of the DG since it isn't a migrated object but a created one. Therefore, I suppose people who use Autocomplete (meaning everybody ^^) will be screwed.
Users will have to get the DG from the Online GAL, correct?
Thanks in advance for your answer
- TonyRedmondAug 16, 2018MVP
If you have a bunch of DLs on-premises, you will need to:
1. Recreate them in the cloud.
2. Delete them on-premises.
If you don't do this, you'll end up having to keep an on-premises server to manage the objects that remain there. It is easy enough to script the recreation and deletion with PowerShell. You'll need to have a session connected to both on-premises and the cloud when you run it.
- AusSupport180Feb 27, 2024Brass ContributorHi Tony,
How do we create a dynamic group? we don't want to update manually.
Setup: Hybid Mode| EXO | Cloud Sync |Azure P2
- SimarSep 24, 2017Copper Contributor
Can you please elaborate more on, "how to export DL (on-premises) and then create in Cloud using PowerShell"?
Thanks!
- TonyRedmondSep 25, 2017MVP
Use the Get-DistributionGroupMember to get the membership of the on-prem DL and then create the new DL inside Exchange Online (a cloud object) before populating its membership (Add-DistributionGroupMember) with the objects you fetched from the original DL. You can connect PowerShell to both the on-prem and cloud environments at the same time, so you can run these commands in a single session.