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Unable to Remove Failed Server from DAG in Exchange Server 2013 RRS feed

  • Question

  • Hello

    We have a DAG with 2 Database server and one Witness server and Domain Controller with tow server.

    All server fail and these servers are virtual. We recover just one database server snapshot by Vmware and tow other servers is not recoverable. From tow Active Directory one A.D. server is recovered and another is not recoverable. All server ping eacth other and successfully authenticate with A.D. .

    In thisconditions database server that is recovered have Primary Active Manager and all services is in running state.

    But I can not remove fail database from DAG!!!

    Please help me.



    • Edited by Mehdi Adibi Tuesday, February 18, 2020 10:52 AM
    Saturday, February 15, 2020 12:40 PM

All replies

  • Hello

    We have a DAG with 2 Database server and one Withness server and Domain Controller with tow server.

    All server fail and these servers are virtual. We recover just one database server snapshot by Vmware and tow other servers is not recoverable. From tow Active Directory one A.D. server is recovered and another is not recoverable. All server ping eacth other and successfully authenticate with A.D. .

    In thisconditions database server that is recovered have Primary Active Manager and all services is in running state.

    But I can not remove fail database from DAG!!!

    Please help me.


    What exactly are you trying to do and what exactly have you done so far to try and remove? Are you trying to remove the server or the database? What commands are using? What happens when you run them and what are the exact errors? Need specific and complete information on the current state of the DAG and what you are trying to accomplish.

    Saturday, February 15, 2020 12:46 PM
  • I type this command to remove fail database server (MAILDB01):

    Remove-DatabaseAvailabilityGroupServer -Identity DAG-Name -MailboxServer MAILDB01 -ConfigurationOnly
    Then this error shows:

    Mailbox server can not be removed from Database Availability Group because mailbox database 'MBX01' has multiple copies. Use Remove-MailboxDatabaseCopy either to remove copy from this server or remove the copies from other servers in Database Availability Group.

    Then I use this command:

    Remove-MailboxDatabaseCopy -Identity MAILDB01\MBX01

    Then this error arise ('MAILDC01' is failed A.D. server and 'MAILDB01' is failed database server):

    The operation could not be performed, because object 'MAILDB01\MBX01' could not be found on 'MAILDC01'.









    • Edited by Mehdi Adibi Sunday, February 16, 2020 7:57 AM
    Sunday, February 16, 2020 7:52 AM
  • It should be noted that DAC is not enabled at installation time of DAG. DAC is not enable yet...
    Sunday, February 16, 2020 12:01 PM
  • Follow these steps.

    https://practical365.com/exchange-server/recovering-a-failed-exchange-2016-database-availability-group-member/

    I would expect errors to be thrown, but still run through them to remove the DB copies first, then the server then evict the node

    Sunday, February 16, 2020 1:40 PM
  • I use recommended command on this link:

    https://practical365.com/exchange-server/recovering-a-failed-exchange-2016-database-availability-group-member/

    That is this command:

    Get-MailboxDatabaseCopyStatus -Server MAILDB01 | Remove-MailboxDatabaseCopy -Confirm:$false

    Then this error arise:

    The database "MBX01" is currently hosted on server "MAILDB01". Use Move-ActiveMailboxDatabase to move the active copy of the database to a different server. You can Remove-MailboxDatabase task if this is the only copy.

    I use this recommended command ("MAILMSWDB02" is recovered database server):

    Move-ActiveMailboxDatabase -Identity MBX01 -ActivateOnServer MAILDB02 -SkipActiveCopyCheck

    Then this error arise:

    Active Manager is not reachable on "MAILMSWDB01". The Microsoft Exchange Replication service might not be running. Error 0x6ba (The RPC server is unavailable) from cli_GetPrimaryActiveManager.



    • Edited by Mehdi Adibi Monday, February 17, 2020 10:06 AM
    Monday, February 17, 2020 5:50 AM
  • Hi,

    What's the detailed version of your Exchange 2013?

    Do you mean you have a DAG with two member servers, and only one member is available at present?

    If MAILMSWDB02 is the member server which is available, please try to restart Microsoft Exchange Replication service and Microsoft Exchange Active Directory Topology service on this server. Then try to move the active mailbox database again.

    Please also make sure the witness server works well and is available.

    Regards,

    Lydia Zhou


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

    • Marked as answer by Mehdi Adibi Monday, February 17, 2020 9:49 AM
    • Unmarked as answer by Mehdi Adibi Monday, February 17, 2020 9:50 AM
    • Marked as answer by Mehdi Adibi Monday, February 17, 2020 9:50 AM
    • Unmarked as answer by Mehdi Adibi Monday, February 17, 2020 9:50 AM
    Monday, February 17, 2020 9:16 AM
  • The witness server dose not work well and is not available.

    Monday, February 17, 2020 9:52 AM
  • I have a DAG with two member servers (MAILDB01 and MAILDB02), and only one member is available at present (MAILDB02).

    All server (Database & Client Access & Edge & Active Directory ) failed and some of them that is expressed below is recovered.

    This is thepresent situation:

    Databases:

         MAILDB01 ---> fail

         MAILDB02 ---> recovered

         Witness    ---> fail

    Domain Controller:

        MAILDC01 ---> recovered

        MAILDC02 ---> fail

    Client Access:

        MAILCAS01 ---> recovered

        MAILCAS02 ---> fail

    Edge:

       MAILEDG01 ---> fail

       MAILEDG02 ---> recovered


    MAILDB02 is the member server which is available, And I try to restart "Microsoft Exchange Replication" service and "Microsoft Exchange Active Directory Topology" service on this server. Then try to move the active mailbox database again with this command:

    Move-ActiveMailboxDatabase -Identity MBX01 -ActivateOnServer MAILDB02 -SkipActiveCopyCheck

    But this error arise again:

    Active Manager is not reachable on "MAILMSWDB01". The Microsoft Exchange Replication service might not be running. Error 0x6ba (The RPC server is unavailable) from cli_GetPrimaryActiveManager.

    • Edited by Mehdi Adibi Monday, February 17, 2020 10:41 AM
    Monday, February 17, 2020 10:02 AM
  • What does the MAILMSWDB01 refer to? Which server is it?

    Additionally, please try to specify another witness server and make it available. Since your DAG has two members, a witness server is needed to act as a tie-breaker, and at least 2 voters must be able to communicate with each other to get the quorum. For more details about quorum: Database availability group (DAG) quorum models

    Regards,

    Lydia Zhou


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

    Tuesday, February 18, 2020 7:53 AM
  • My DAG has one members (MAILDB02), because another member (MAILDB01) is not recoverable and is not accessible.

    Witness is not recoverable too.

    I must up my mail server just with one database and one A.D. server.


    • Edited by Mehdi Adibi Tuesday, February 18, 2020 10:48 AM
    Tuesday, February 18, 2020 10:46 AM
  • My DAG has one members (MAILDB02), because another member (MAILDB01) is not recoverable and is not accessible.

    Witness is not recoverable too.

    I must up my mail server just with one database and one A.D. server.


    I think its time to open a support case directly with Microsoft. The Forums are not a good place to troubleshoot these issues sometimes.
    Tuesday, February 18, 2020 12:45 PM
  • Though one DAG member is down, this doesn't mean your DAG only have one member. Does this unaccessible server still exist in AD?

    You also can use the following to check you DAG members:

    Get-DatabaseAvailabilityGroup <DAGName> | Format-List Servers

    As is mentioned, you have to specify another server as your new witness server and make it available. We have to make sure your DAG works, then try to remove the failed member server from DAG.

    Regards,

    Lydia Zhou


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

    Thursday, February 20, 2020 5:00 AM
  • Any updates so far? If you have solved your problem, could you share with us? Maybe it will help more people with similar problems. 

    Regards,

    Lydia Zhou


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

    Wednesday, February 26, 2020 8:58 AM
  • Here is a brief summary about replies above, hope more people can get information from it.

    Issue Symptoms:

    We have a DAG with 2 Database server and one Witness server and Domain Controller with tow server.

    All server fail and these servers are virtual. We recover just one database server snapshot by Vmware and tow other servers is not recoverable. From tow Active Directory one A.D. server is recovered and another is not recoverable. All server ping eacth other and successfully authenticate with A.D. .

    In this conditions database server that is recovered have Primary Active Manager and all services is in running state. But I can not remove fail database from DAG.

    Possible Cause:

    This issue may be caused by the DAG cannot get the quorum.

    Troubleshooting Steps so far:

    If MAILMSWDB02 is the member server which is available, please try to restart Microsoft Exchange Replication service and Microsoft Exchange Active Directory Topology service on this server. Then try to move the active mailbox database again.

    Please try to specify another witness server and make it available. Since your DAG has two members, a witness server is needed to act as a tie-breaker, and at least 2 voters must be able to communicate with each other to get the quorum. 

    Next Step:

    You also can use the following to check you DAG members:

    Get-DatabaseAvailabilityGroup <DAGName> | Format-List Servers 

    As is mentioned, you have to specify another server as your new witness server and make it available. We have to make sure your DAG works, then try to remove the failed member server from DAG.

    Reference Link:

    Database availability group (DAG) quorum models

    Regards,

    Lydia Zhou


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

    Wednesday, March 4, 2020 1:13 AM