Posts tagged ‘exchange hybrid’
How to offboard Exchange Online Mailboxes to Exchange On-Prem using Exchange Hybrid Environment
Recently , we had a project to offboard Exchange Online Mailboxes to On-Prem Exchange. In this environment customer already have Entra Connect Server. I would like to share the steps we followed during the project so it could be referred by anybody who is having a similar requirements.
However , I am not going to list out any commands here as it is freely available in many web sites.
- First we deployed Exchange On-Prem Server and completed all the configuration like DAG , Connector etc.
- Then we deployed the Exchange hybrid Configurations with Centralized Mail Transport.
- All the autodiscover,MX and other Exchange related DNS records were re-pointed to Exchange On-Prem Public IP’s.
- Created a TestMailbox in Exchange On-Prem and tested the email flow.
– Email sent to Exchange On-Prem Mailbox from Outside delivered successfully.
– Email sent to ExchangeOnline Mailbox from outside bounced back with an error user not found in the organization.
– Email tests sent from Exchange On-Prem to Exchange Online and vice versa failed. - After troubleshooting we found out the Exchange Online mailboxes were not visible on Exchange-On-Prem ECP. Further troubleshooting revealed that the AD user attribute for the AD synced users does not have Remote Routing Address.(e.g testdomain.mail.onmicrosoft.com)
- So we decided to do a bulk update of all the users to populate their Remote Routing Address.(You must do a Delta AD Sync after this process). Thereafter , we were able to see all the Exchange Online Mailboxes in the Exchange On-Prem ECP.
- Tested all the email scenarios and confirmed everything is working fine.
- The other obstacle we faced is that , when an email sent from Exchange Online Mailboxes to outside world the relaying was denied by the Exchange On-Prem server.Even though , we believed the default FrontEnd receive connector in Exchange On-Prem had all the requirement for this, we ended up creating a new Receive Connector and added all the Exchange Online IP’s to allow the email relay and resume the e-mail flow.
Hope it helps some one who is struggling to find a proper article for similar scenario. In case , if you want to reach out to me for detailed steps like commands used for bulk import/export/AD properties update , please feel free to reach out to me.
How to Remove office 365 mailbox without deleting user account
We were planning to deploy an Exchange Hybrid Configuration with On-Premise Exchange 2019 servers. Thereafter , we will be moving some of the mailboxes to On-Premise Exchange
Servers and disable only the Exchange Online mailbox to keep the user account intact with the license so he could use other Applications (like SharePoint Online , OneDrive and Desktop Apps ,etc).
The environment is already synced via Azure AD Connect.
Since the Exchange Online license is assigned to the user , the user could have one mailbox in Office 365 and one in an on-premises Exchange ,causing mail delivery issues . Thus , to solve the issue
we need to
1) Remove the Exchange Online License for the user.
2) Clear the mailbox info:
Set-User user@tga.gov.sa -PermanentlyClearPreviousMailboxInfo
3) Resync and Ensure the MSExchangeGuid is Synced to point that now the Mailbox is in On-Premise Server.
4) Re-assign the Exchange Online License in O365.
5) Now the user will not be having a mailbox , But, he will be able to access the SharepointOnline , OneDrive , the DesktopApps , etc.
OR , we could use the below steps as well (Recommended by the MS Support)
– Migrate the O365 mailbox to On-Premise Exchange Server.
– Go to the License & Apps under the User property in O365 portal.
– Unselect the Exchange Online (Plan 2) from the Apps list.
– This will ensure that the user mailbox is only in On-Premise Exchange Server and still he will be able to access the SharepointOnline, OneDrive and DesktopApp ,etc)
Hope you like it.. 