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Exchange 2010 dag Replication Error

I've just recently setup DAG for our Exchange 2010 servers, it has 3 databases and 2 Exchange 2010 servers (Primary and Failover). The DAG does not work and I'm getting this error in the Event Viewer on the primary Exchange server.

Redundancy health check fails with the following error:

The number of configured copies for database (1) is less than the required redundancy count (2)

Any help would be greatly appreciated.

Manpreet SIngh Khatra

There is some DB in DAG that has only one DB copy if you can check and share somescreenshot or correct it .... if some Test DB please ignore

- Rancy

ASKER

Sorry I'm not real familiar with DAG, where can I check to see the number of DB copies?

Open EMS or Exchange Management Shell. Paste below command's and post the result.

Command 1
Test-ReplicationHealth

Command 2
Get-MailboxDatabase | ft name, server, activationpreference -AutoSize

ASKER

The Database Availability Groups tab in the Exchange Management Consoles shows the name of my DAG and Member Servers A and B also shows the path for the Witness directory.

Use above command. Or click on DB tab.

ASKER

[PS] C:\Windows\system32>test-replicationhealth

Server Check Result Error
------ ----- ------ -----
Server A        ClusterService Passed
Server A ReplayService Passed
Server A ActiveManager Passed
Server A TasksRpcListener Passed
Server A TcpListener Passed
Server A DagMembersUp Passed
Server A ClusterNetwork Passed
Server A QuorumGroup Passed
Server A FileShareQuorum Passed

[PS] C:\Windows\system32>get-mailboxdatabase | ft name, server, acitvationpref

Name Server acitvationpreference
---- ------ --------------------
Database A Server A
Database B       Server A
Database C      Server A

[PS] C:\Windows\system32>

I don't see any copy has been created. You need same size disk setting on Server B and then add the copy.

ASKER

Ok, how do I add the db copies to server B ?

Walk through this article
http://exchangeserverpro.com/exchange-server-2010-database-availability-group-installation-step-by-step

Manpreet SIngh Khatra

try the below command

Get-MailboxDatabase | Get-MailboxDatabaseCopyStatus

or else go to EMC -> Org Confi -> Mailbox and check each mailboxDB or share a screenshot with me .... however the error has the concerned DB name

- Rancy

ASKER

[PS] C:\Windows\system32>get-mailboxdatabase | get-mailboxdatabasecopystatus

Name Status CopyQueue ReplayQueue LtInspLogTime ContIdx
Length Length State
---------------------------- ------ --------- ----------- -------------------- ------------
Database A\Server A Mounted 0 0 Healthy
Database B\Server A Mounted 0 0 Healthy
Database C\Server A Mounted 0 0 Healthy

Also I'm reading over the Exchserverpro info you sent, thanks.

ASKER

Ok, read through the article, at the point where I'm copying the database from Server A to ServerB. The copy status says "Failed" with this information.

The required log file 38247 for DatabaseA\ServerB is missing on the active copy. If you removed the log file, please replace it. If the log file is lost, the database copy will need to be reseeded using Update-MailboxDatabaseCopy.

Manpreet SIngh Khatra

Perfect yes what it means is if some data is removed from Active and it caused a Brain split to DB and also lets say if there was 2000 logs in Active and same in Passive and if for some reason Admin deleted some logs from Active this will again need reseed as Passive wont work or atleast Backup wont purge logs again requiring Logs to be reset and this again requires DB on Passive to be reseeded

- Rancy

ASKER

Ok, so do I need to just run "Update-MailboxDatabaseCopy" on destination server B?
Do I need to delete the "failed" database first, the run the update?
Do you know the command syntax to only update Database A?

ASKER

Nevermind, I think I figured it out, I can simple right click on the failed database and select Suspened and Resume database copy. Right now the copy status is "Resynchronizing".

ASKER

I think the db is stuck in "Resynchronizing" mode. Anyway to fix this?

ASKER

Should I be able to see database copies on both ServerA and ServerB? I can only see db copies on ServerB (the failover server) I cannot see them on ServerA.

ASKER

Sorry, not db copies I meant DAG networks. Should I be able to see DAG networks on both ServerA and ServerB? I can only see DAG networks on ServerB (the failover server) I cannot see it on ServerA.

Manpreet SIngh Khatra

Should I be able to see database copies on both ServerA and ServerB? I can only see db copies on ServerB (the failover server) I cannot see them on ServerA - ServerA is Active so it has to be there and ServerB is taking a copy so will be seen once the completion happens

Sorry, not db copies I meant DAG networks. Should I be able to see DAG networks on both ServerA and ServerB? I can only see DAG networks on ServerB (the failover server) I cannot see it on ServerA - Its fine check when you do a failover as it should be on the Passive that will use to Log ship for DAG copies

- Rancy

ASKER

What is the easiest way to test a fail-over?

Manpreet SIngh Khatra

Right click on the Database in EMC and move to passive node

- Rancy

ASKER

But doesn't that just make the passive copy of the DB active on the Server B, and Exchange is still running from Server A?

Manpreet SIngh Khatra

Yes if you want an entire failover either take down ServerA or else move Resources to ServerB

- Rancy

ASKER

I disconnect the network NIC on ServerA and it did not fail-over to serverB.

Manpreet SIngh Khatra

Is that the only NIC why dont you simply do ServerA restart or Move using Cluster

- Rancy

ASKER

Looks likes a problem on the witness server.
Server Check Result Error
------ ----- ------ -----
DCSOSVMS03 ClusterService Passed
DCSOSVMS03 ReplayService Passed
DCSOSVMS03 ActiveManager Passed
DCSOSVMS03 TasksRpcListener Passed
DCSOSVMS03 TcpListener Passed
DCSOSVMS03 DagMembersUp Passed
DCSOSVMS03 ClusterNetwork Passed
DCSOSVMS03 QuorumGroup *FAILED* Quorum resource 'Cluster Group' is not online on server 'dcsos...
DCSOSVMS03 FileShareQuorum *FAILED* Couldn't access file share witness share '\\dcsosvbackup.dcso....
DCSOSVMS03 DBCopySuspended Passed
DCSOSVMS03 DBCopyFailed Passed
DCSOSVMS03 DBInitializing Passed
DCSOSVMS03 DBDisconnected Passed
DCSOSVMS03 DBLogCopyKeepingUp Passed
DCSOSVMS03 DBLogReplayKeepingUp Passed

Manpreet SIngh Khatra

DCSOSVMS03 FileShareQuorum *FAILED* Couldn't access file share witness share '\\dcsosvbackup.dcso....

you can try this
Cluster Group "QuorumGroup" /Online:NodeName

- Rancy

ASKER

System error 5013 has occured, the cluster group could not be found.

Manpreet SIngh Khatra

Please check and ensure the FSW is accessible and then work to get the Resources online

- Rancy

ASKER

I think the problem is I cannot access the FSW server using the server's FQDN name (FSWserver.domain.com) and that's how the Cluster Quorum is try to access it. Now if I can only figure out why.

Manpreet SIngh Khatra

Check DNS entires and hope everything is working fine

- Rancy

ASKER

Ok, problem was FSW server did not have a DNS reservation. Now unplugging the NIC cable on Exchange serverA will automatically mount the DB on Exchanger serverB after waiting a few minutes. Then after waiting a few more minutes more my Outlook client reconnected to the failover Exchange serverB. This is perfect!

ASKER

Question: When I connect ServerA back to the network, will the database automatically mount back on ServerA ? Will the Outlook clients automatically connect back to serverA?

Manpreet SIngh Khatra

There is no Automatic Failover its more of when there is issue on one node it fails to another or you have manually

- Rancy

ASKER

I can right click on the mailbox server database and mount it back on primary ServerA. But the Outlook clients still remain connected to ServerB. Is there an easier way to make the Outlook clients connect back to ServerA without having to disconnect the network cable on ServerB or shut it down? Rebooting ServerB does not make the clients connect back to ServerA.

ASKER CERTIFIED SOLUTION

Manpreet SIngh Khatra

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ASKER

Ok, thanks for all your help.