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Steps to decommission Hybrid Office 365 - Exchange DAG without downtime? RRS feed

  • Question

  • Hi All,

    I am using the hybrid Office 365 and multiple Exchange servers 2013 SP1 CU15 that is running DAG across multiple AD sites and DataCentre.

    AD Site1 - City A:
    OnPrem Mailboxes: 55 User remaining

    AD Site2 - City B:
    OnPrem Mailboxes: 49 User remaining

    AD Site3 - City C:
    OnPrem Mailboxes: 17 User remaining

    AD Site4 - City D:
    OnPrem Mailboxes: 62 User remaining

    There are still some mailboxes that reside in the mailbox DB which I will migrate next week or so.

    So, what's the best steps to decommission the DAG nodes above while still keeping the 2x CAS servers nodes in AD Site2 - City B and AD Site4 - City D for Exchange mailbox operations without impacting the hybrid email flow?

    Thanks in advance.

    /* Server Support Specialist */

    Monday, July 22, 2019 3:59 AM

Answers

  • It depend on whether you retain the sync with Azure AD.

    If you want retain the sync with Azure AD, we recommend you to leave at least one Exchange server, since when directory synchronization is enabled for a tenant and a user is synchronized from on-premises, most of the attributes cannot be managed from Exchange Online and must be managed from on-premises. Besides, the Exchange Management Console, the Exchange admin center (EAC), and the Exchange Management Shell are the only supported tools that are available to manage Exchange recipients and objects. 

    Regards,

    Manu Meng


    Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact tnsf@microsoft.com.

    Thursday, July 25, 2019 6:54 AM
    Moderator
  • It depend on whether you retain the sync with Azure AD.

    If you want retain the sync with Azure AD, we recommend you to leave at least one Exchange server, since when directory synchronization is enabled for a tenant and a user is synchronized from on-premises, most of the attributes cannot be managed from Exchange Online and must be managed from on-premises. Besides, the Exchange Management Console, the Exchange admin center (EAC), and the Exchange Management Shell are the only supported tools that are available to manage Exchange recipients and objects. 

    Regards,

    Manu Meng


    Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact tnsf@microsoft.com.

    OK,

    Can I upgrade the OnPremise Exchange CAS server to Exchange Server 2019 from 2013 to make it supportable?


    /* Server Support Specialist */

    Yes, you can, but Exchange 2013 is also supported, other option is upgrading Exchange 2013 to the latest version.

    Regards,

    Manu Meng


    Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact tnsf@microsoft.com.

    Thursday, July 25, 2019 7:01 AM
    Moderator

All replies

  • After the migration is completed and all mailboxes are in the cloud side, you could point your MX records and Autodiscover to EOP.

    For more details, please refer to the Scenario two in the following article:

    How and when to decommission your on-premises Exchange servers in a hybrid deployment

    Regards,

    Manu Meng


    Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact tnsf@microsoft.com.

    Tuesday, July 23, 2019 7:29 AM
    Moderator
  • After the migration is completed and all mailboxes are in the cloud side, you could point your MX records and Autodiscover to EOP.

    For more details, please refer to the Scenario two in the following article:

    How and when to decommission your on-premises Exchange servers in a hybrid deployment

    Regards,

    Manu Meng


    Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact tnsf@microsoft.com.

    Hi Manu,

    So after deleting the last mailbox DB, I assume I can just uninstall the Exchange server from the OnPremise?

    or do I still need to retain the CAS server role to ensure I still be able to use Hybrid - Synced identity with Azure AD?


    /* Server Support Specialist */

    Wednesday, July 24, 2019 2:11 PM
  • It depend on whether you retain the sync with Azure AD.

    If you want retain the sync with Azure AD, we recommend you to leave at least one Exchange server, since when directory synchronization is enabled for a tenant and a user is synchronized from on-premises, most of the attributes cannot be managed from Exchange Online and must be managed from on-premises. Besides, the Exchange Management Console, the Exchange admin center (EAC), and the Exchange Management Shell are the only supported tools that are available to manage Exchange recipients and objects. 

    Regards,

    Manu Meng


    Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact tnsf@microsoft.com.

    Thursday, July 25, 2019 6:54 AM
    Moderator
  • It depend on whether you retain the sync with Azure AD.

    If you want retain the sync with Azure AD, we recommend you to leave at least one Exchange server, since when directory synchronization is enabled for a tenant and a user is synchronized from on-premises, most of the attributes cannot be managed from Exchange Online and must be managed from on-premises. Besides, the Exchange Management Console, the Exchange admin center (EAC), and the Exchange Management Shell are the only supported tools that are available to manage Exchange recipients and objects. 

    Regards,

    Manu Meng


    Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact tnsf@microsoft.com.

    OK,

    Can I upgrade the OnPremise Exchange CAS server to Exchange Server 2019 from 2013 to make it supportable?


    /* Server Support Specialist */

    Thursday, July 25, 2019 6:56 AM
  • It depend on whether you retain the sync with Azure AD.

    If you want retain the sync with Azure AD, we recommend you to leave at least one Exchange server, since when directory synchronization is enabled for a tenant and a user is synchronized from on-premises, most of the attributes cannot be managed from Exchange Online and must be managed from on-premises. Besides, the Exchange Management Console, the Exchange admin center (EAC), and the Exchange Management Shell are the only supported tools that are available to manage Exchange recipients and objects. 

    Regards,

    Manu Meng


    Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact tnsf@microsoft.com.

    OK,

    Can I upgrade the OnPremise Exchange CAS server to Exchange Server 2019 from 2013 to make it supportable?


    /* Server Support Specialist */

    Yes, you can, but Exchange 2013 is also supported, other option is upgrading Exchange 2013 to the latest version.

    Regards,

    Manu Meng


    Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact tnsf@microsoft.com.

    Thursday, July 25, 2019 7:01 AM
    Moderator
  • It depend on whether you retain the sync with Azure AD.

    If you want retain the sync with Azure AD, we recommend you to leave at least one Exchange server, since when directory synchronization is enabled for a tenant and a user is synchronized from on-premises, most of the attributes cannot be managed from Exchange Online and must be managed from on-premises. Besides, the Exchange Management Console, the Exchange admin center (EAC), and the Exchange Management Shell are the only supported tools that are available to manage Exchange recipients and objects. 

    Regards,

    Manu Meng


    Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact tnsf@microsoft.com.

    OK,

    Can I upgrade the OnPremise Exchange CAS server to Exchange Server 2019 from 2013 to make it supportable?


    /* Server Support Specialist */

    Yes, you can, but Exchange 2013 is also supported, other option is upgrading Exchange 2013 to the latest version.

    Regards,

    Manu Meng


    Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact tnsf@microsoft.com.

    Yes, that is exactly what I am after.

    So if I just upgrade the Exchange Server 2013 to 2019 after removing all of the mailboxes, it is the supported way to modify the Synchronized AD attributes for Hybrid.


    /* Server Support Specialist */

    Friday, July 26, 2019 2:24 AM