Hi all,
I'm having an issue creating a DAG in Exchange 2013.
We have a CAS Server which is also our witness server and 2 mailbox servers. All servers running Windows Server 2012 Standard, Exchange 2013 + CU3.
 
When I try to add the mailbox servers into the DAG I get the following error message:

A server-side database availability group administrative operation failed. Error The operation failed. CreateCluster errors may result from incorrectly configured static addresses. Error: Computer account 'EXCDAG13' couldn't be validated by user 'NT AUTHORITY\SYSTEM'. Error: Unknown error (0xc000018b). [Server: EXCMB1.contoso.local]
 
A server-side database availability group administrative operation failed. Error The operation failed. CreateCluster errors may result from incorrectly configured static addresses. Error: Computer account 'EXCDAG13' couldn't be validated by user 'NT AUTHORITY\SYSTEM'. Error: Unknown error (0xc000018b). [Server: EXCMB2.contoso.local]
 
I have followed all the correct steps:

Step 1 Pre-Stage DAG Computer Account
- Created a Computer Account in AD with the name of the DAG
- Disabled the Computer Account
- Granted the Exchange Trusted Subsystem group Full Control permissions
- Although this step isnt necessary as I did the step above, I also added in the Computer Account of the first node EXCMB1.contoso.local and Granted Full Control permissions

Step 2 Configure DAG NICs
- Configured a MAPI/Replication network

EXCMB1.contoso.local:
 MAPI Network 172.19.220.45 Subnet Mask 255.255.255.0 Default Gateway 172.19.220.250
 Replication Network 10.1.1.1 Subnet Mask 255.255.255.0 Default Gateway NONE

EXCMB2.contoso.local:
 MAPI Network 172.19.220.46 Subnet Mask 255.255.255.0 Default Gateway 172.19.220.250
 Replication Network 10.1.1.2 Subnet Mask 255.255.255.0 Default Gateway NONE

- Configured the NIC Binding Order
- Unchecked register this connections address in DNS for the Replications Replication Networks
- Verified network connectivity is ok with the MAPI/Replication networks

Step 3 Create DAG & Add Nodes
- Give the DAG a static IP Address of 172.19.220.47

I have gone through heaps of articles online and I am yet to come across anyone who has had the same error as me?
Any help will be highly appreciated.

Thank you

• Edited by PO_IT_Support Thursday, January 02, 2014 11:57 PM

Hi,

I recommend you follow the steps below for troubleshooting:

1. Please ensure that the account you use to add DAG members has permissions to "Create Computer Objects".

2. Give Exchange Trusted Subsystem and administrator full control on Cluster Name Object.

3. Disable TCP Chimney Offload and RSS.

4. Disable all the firewall temporarily.

After finishing the above steps, please add the Mailbox server to DAG and see the result.

Hope it helps.

If there are any problems, please feel free to let me know.

Best regards,
Amy

Hello Amy,

Regarding Disabling TCP Chimney Offload and RSS.

On which server should I run this on? The witness server, mailbox server or both?

To confirm these are the commands I need to run?

netsh int tcp set global rss=disabled
netsh int tcp set global chimney=disabled

Appreciate your help.

Thank you

Hi all,

Please note I'm still having issues adding mailbox servers to the DAG.

I disabled TCP Chimney Offload and RSS on all the servers but it made no difference.

I'm still getting the same error:

A server-side database availability group administrative operation failed. Error The operation failed. CreateCluster errors may result from incorrectly configured static addresses. Error: Computer account 'EXCDAG13' couldn't be validated by user 'NT AUTHORITY\SYSTEM'. Error: Unknown error (0xc000018b). [Server: EXCMB1.contoso.local]
 
A server-side database availability group administrative operation failed. Error The operation failed. CreateCluster errors may result from incorrectly configured static addresses. Error: Computer account 'EXCDAG13' couldn't be validated by user 'NT AUTHORITY\SYSTEM'. Error: Unknown error (0xc000018b). [Server: EXCMB2.contoso.local]

PLEASE HELP ANYONE?????

Thank you

Hi,

1. Please make sure that the following ports are opened:

389/TCP/UDP (LDAP), 3268/TCP (LDAP GC), 88/TCP/UDP (Kerberos), 53/TCP/UDP (DNS), 135/TCP (RPC), 445/TCP (SMB), 64327/TCP (Log shipping), 3343/UDP (cluster node communication), 1024-65535/TCP (Dynamic RPC over TCP to communicate cluster status and activity between the different cluster nodes).

2. Please ensure Failover Clustering is installed.

3. From the error "CreateCluster errors may result from incorrectly configured static addresses", network configuration is incorrect. Please recreate the DAG using correct network configuration.

Here are some articles for your reference.

Managing Database Availability Groups

http://technet.microsoft.com/en-us/library/dd298065(v=exchg.150)#Dat

Create a Database Availability Group

http://technet.microsoft.com/en-us/library/dd351172(v=exchg.150).aspx

Hope it helps.

If you need further assistance, please feel free to let me know.

Best regards,
Amy

Can you check the DagTasks folder and the log in there to see if there is anything logged in there ?

Check if the following were enabled or not on the DAG NICs:
Link-Layer Topology Discovery Mapper I/O Driver
Link-Layer Topology Discovery Responder

From my research this issue can also be caused if IPv6 is only unchecked on the NIC but not disabled correctly in the registry, see KB929852.

See the "Network Requirements" section for full details Planning for High Availability and Site Resilience - http://technet.microsoft.com/en-us/library/dd638104.aspx

Hello Pavan Maganti,

I can confirm that following below were enabled on the DAG NICs:
Link-Layer Topology Discovery Mapper I/O Driver
Link-Layer Topology Discovery Responder

I then checked the registry to ensure IPv6 was enabled.
I notice there was no "DisabledComponents" registry subkey on all Exchnage 2013 servers which made me suspect it could of been something with IPv6 ???

On on all the Exchnage 2013 servers I created a New DWORD (32-bit) Value called DisabledComponents in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip6\Parameters and set the Value data to 0 (this enabling all IPv6 components which apparently is the Windows default setting)

I rebooted all the Exchnage 2013 servers and then tried to add the mailbox servers into the DAG again = It FAILED with the same error message.

Note: This is error log im getting from C:\ExchangeSetupLogs\DagTasks:

add-databaseavailabiltygroupserver started on machine EXCMB1.
[2014-01-02T23:29:02] add-dagserver started
[2014-01-02T23:29:02] commandline:         $scriptCmd = {& $wrappedCmd @PSBoundParameters }

[2014-01-02T23:29:02] Option 'Identity' = 'EXCD13'.
[2014-01-02T23:29:02] Option 'MailboxServer' = 'EXCMB2'.
[2014-01-02T23:29:02] Option 'DatabaseAvailabilityGroupIpAddresses' = ''.
[2014-01-02T23:29:02] Option 'WhatIf' = ''.
[2014-01-02T23:29:02] Process: w3wp w3wp.exe:8452.
[2014-01-02T23:29:02] User context = 'NT AUTHORITY\SYSTEM'.
[2014-01-02T23:29:02]   Member of group 'Everyone'.
[2014-01-02T23:29:02]   Member of group 'EXCMB1\SophosUser'.
[2014-01-02T23:29:02]   Member of group 'BUILTIN\Users'.
[2014-01-02T23:29:02]   Member of group 'NT AUTHORITY\SERVICE'.
[2014-01-02T23:29:02]   Member of group 'CONSOLE LOGON'.
[2014-01-02T23:29:02]   Member of group 'NT AUTHORITY\Authenticated Users'.
[2014-01-02T23:29:02]   Member of group 'NT AUTHORITY\This Organization'.
[2014-01-02T23:29:02]   Member of group 'BUILTIN\IIS_IUSRS'.
[2014-01-02T23:29:02]   Member of group 'LOCAL'.
[2014-01-02T23:29:02]   Member of group 'IIS APPPOOL\MSExchangeECPAppPool'.
[2014-01-02T23:29:02]   Member of group 'BUILTIN\Administrators'.
[2014-01-02T23:29:02] Updated Progress 'Validating the parameters.' 2%.
[2014-01-02T23:29:02] Working
[2014-01-02T23:29:02] Mailbox server: value passed in = EXCMB2, mailboxServer.Name = EXCMB2, mailboxServer.Fqdn = EXCMB2.contoso.local
[2014-01-02T23:29:02] LogClussvcState: clussvc is Stopped on EXCMB2.contoso.local. Exception (if any) = none
[2014-01-02T23:29:02] The IP addresses for the DAG are (blank means DHCP): 172.19.220.47
[2014-01-02T23:29:02] Looking up IP addresses for EXCD13.
[2014-01-02T23:29:04] Failure while trying to resolve EXCD13: threw a SocketException: No such host is known.
[2014-01-02T23:29:04] Looking up IP addresses for excmb2.
[2014-01-02T23:29:04]   excmb2 = [ 172.19.220.46 ].
[2014-01-02T23:29:04] Looking up IP addresses for EXCMB2.contoso.local.
[2014-01-02T23:29:04]   EXCMB2.contoso.local = [ 172.19.220.46 ].
[2014-01-02T23:29:04] DAG EXCD13 has 0 servers:
[2014-01-02T23:29:04] Updated Progress 'Checking if Mailbox server 'EXCMB2' is in a database availability group.' 4%.
[2014-01-02T23:29:04] Working
[2014-01-02T23:29:04] GetRemoteCluster() for the mailbox server failed with exception = An Active Manager operation failed. Error: An error occurred while attempting a cluster operation. Error: Cluster API '"OpenCluster(EXCMB2.contoso.local) failed with 0x6d9. Error: There are no more endpoints available from the endpoint mapper"' failed.. This is OK.
[2014-01-02T23:29:04] Ignoring previous error, as it is acceptable if the cluster does not exist yet.
[2014-01-02T23:29:04] DumpClusterTopology: Opening remote cluster EXCD13.
[2014-01-02T23:29:04] DumpClusterTopology: Failed opening with Microsoft.Exchange.Cluster.Replay.AmGetFqdnFailedNotFoundException: An Active Manager operation failed with a transient error. Please retry the operation. Error: The fully qualified domain name for node 'EXCD13' could not be found.
   at Microsoft.Exchange.Cluster.ActiveManagerServer.AmServerNameCache.<>c__DisplayClass1.<ResolveFqdn>b__0(Object param0, EventArgs param1)
   at Microsoft.Exchange.Cluster.ActiveManagerServer.AmHelper.RunADOperationEx(EventHandler ev)
   at Microsoft.Exchange.Cluster.ActiveManagerServer.AmServerNameCache.ResolveFqdn(String shortNodeName, Boolean throwException)
   at Microsoft.Exchange.Cluster.ActiveManagerServer.AmServerNameCache.GetFqdn(String shortNodeName, Boolean throwException)
   at Microsoft.Exchange.Cluster.ActiveManagerServer.AmServerName..ctor(String serverName, Boolean throwOnFqdnError)
   at Microsoft.Exchange.Management.SystemConfigurationTasks.DumpClusterTopology..ctor(String nameCluster, ITaskOutputHelper output)
[2014-01-02T23:29:04] Dumping the cluster by connecting to: EXCD13.
[2014-01-02T23:29:04] DumpClusterTopology: Not dumping, since the cluster could not be contacted.
[2014-01-02T23:29:04] The new server (EXCMB2) is not a member of a cluster, nor are the other servers (if there are any other servers).
[2014-01-02T23:29:04] The computer account EXCD13 does not exist.
[2014-01-02T23:29:04] According to GetNodeClusterState(), the server EXCMB2 is NotConfigured.
[2014-01-02T23:29:04] InternalValidate() done.
[2014-01-02T23:29:04] Updated Progress 'Adding server 'EXCMB2' to database availability group 'EXCD13'.' 6%.
[2014-01-02T23:29:04] Working
[2014-01-02T23:29:04] Connecting to server 'EXCMB2.contoso.local' via WMI...
[2014-01-02T23:29:05] Fetching the network adapters and including the ones without default gateways.
[2014-01-02T23:29:05] EXCMB2.contoso.local has an address: 172.19.220.46/24 default gateway(s)=172.19.220.250 [valid]
[2014-01-02T23:29:05] IP address derived that's suitable for clustering DHCP/IPv6: 172.19.220.0/24.
[2014-01-02T23:29:05] EXCMB2.contoso.local has an address: fe80::30a5:ab07:f05:d10c/64 default gateway(s)=172.19.220.250 [invalid]
[2014-01-02T23:29:05] EXCMB2.contoso.local has an address: 10.1.1.2/24 default gateway(s)=<none> [valid]
[2014-01-02T23:29:05] IP address derived that's suitable for clustering DHCP/IPv6: 10.1.1.0/24.
[2014-01-02T23:29:05] EXCMB2.contoso.local has an address: fe80::91ec:7d06:8415:73a3/64 default gateway(s)=<none> [invalid]
[2014-01-02T23:29:05] The address 172.19.220.47 falls under the network (172.19.220.0/24).
[2014-01-02T23:29:05] Updated Progress 'Forming cluster named 'EXCD13' on server 'EXCMB2'.' 8%.
[2014-01-02T23:29:05] Working
[2014-01-02T23:29:05] Forming cluster named 'EXCD13' on server 'EXCMB2'. The cluster address is/are [172.19.220.47], and the cluster network prefix length is/are [24].
[2014-01-02T23:29:07] The following log entry comes from a different process that's running on machine 'EXCMB2'. BEGIN
[2014-01-02T23:29:07] [2014-01-02T23:29:07] Updated Progress 'Forming cluster named 'EXCD13' on server 'excmb2'.' 2%.
[2014-01-02T23:29:07] Working
[2014-01-02T23:29:07] ClusterSetupProgressCallback( eSetupPhase = ClusterSetupPhaseInitialize, ePhaseType = ClusterSetupPhaseStart, ePhaseSeverity = ClusterSetupPhaseInformational, dwPercentComplete = 5, szObjectName = EXCD13, dwStatus = 0x0 )
[2014-01-02T23:29:07] ClusterSetupProgressCallback( eSetupPhase = ClusterSetupPhaseInitialize, ePhaseType = ClusterSetupPhaseEnd, ePhaseSeverity = ClusterSetupPhaseInformational, dwPercentComplete = 5, szObjectName = , dwStatus = 0x0 )
[2014-01-02T23:29:07] ClusterSetupProgressCallback( eSetupPhase = ClusterSetupPhaseValidateNodeState, ePhaseType = ClusterSetupPhaseStart, ePhaseSeverity = ClusterSetupPhaseInformational, dwPercentComplete = 10, szObjectName = EXCMB2.contoso.local, dwStatus = 0x0 )
[2014-01-02T23:29:08] ClusterSetupProgressCallback( eSetupPhase = ClusterSetupPhaseValidateNodeState, ePhaseType = ClusterSetupPhaseEnd, ePhaseSeverity = ClusterSetupPhaseInformational, dwPercentComplete = 10, szObjectName = , dwStatus = 0x0 )
[2014-01-02T23:29:09] ClusterSetupProgressCallback( eSetupPhase = ClusterSetupPhaseQueryClusterNameAccount, ePhaseType = ClusterSetupPhaseStart, ePhaseSeverity = ClusterSetupPhaseInformational, dwPercentComplete = 15, szObjectName = EXCD13, dwStatus = 0x0 )
[2014-01-02T23:29:09] ClusterSetupProgressCallback( eSetupPhase = ClusterSetupPhaseQueryClusterNameAccount, ePhaseType = ClusterSetupPhaseEnd, ePhaseSeverity = ClusterSetupPhaseInformational, dwPercentComplete = 15, szObjectName = , dwStatus = 0x0 )
[2014-01-02T23:29:09] ClusterSetupProgressCallback( eSetupPhase = ClusterSetupPhaseValidateClusterNameAccount, ePhaseType = ClusterSetupPhaseStart, ePhaseSeverity = ClusterSetupPhaseInformational, dwPercentComplete = 21, szObjectName = EXCD13, dwStatus = 0x0 )
[2014-01-02T23:29:09] ClusterSetupProgressCallback( eSetupPhase = ClusterSetupPhaseValidateClusterNameAccount, ePhaseType = ClusterSetupPhaseEnd, ePhaseSeverity = ClusterSetupPhaseFatal, dwPercentComplete = 21, szObjectName = EXCD13, dwStatus = 0xc000018b )
[2014-01-02T23:29:09] Found a matching exception: Microsoft.Exchange.Cluster.Replay.DagTaskComputerAccountCouldNotBeValidatedException: A server-side database availability group administrative operation failed. Error Computer account 'EXCD13' couldn't be validated by user 'NT AUTHORITY\SYSTEM'. Error: Unknown error (0xc000018b).
[2014-01-02T23:29:09] ClusterSetupProgressCallback( eSetupPhase = ClusterSetupPhaseValidateClusterNameAccount, ePhaseType = ClusterSetupPhaseEnd, ePhaseSeverity = ClusterSetupPhaseFatal, dwPercentComplete = 21, szObjectName = EXCD13, dwStatus = 0xc000018b )
[2014-01-02T23:29:09] Found a matching exception: Microsoft.Exchange.Cluster.Replay.DagTaskComputerAccountCouldNotBeValidatedException: A server-side database availability group administrative operation failed. Error Computer account 'EXCD13' couldn't be validated by user 'NT AUTHORITY\SYSTEM'. Error: Unknown error (0xc000018b).
[2014-01-02T23:29:09] ClusterSetupProgressCallback( eSetupPhase = ClusterSetupPhaseFailureCleanup, ePhaseType = ClusterSetupPhaseStart, ePhaseSeverity = ClusterSetupPhaseInformational, dwPercentComplete = 21, szObjectName = EXCMB2.contoso.local, dwStatus = 0x0 )
[2014-01-02T23:29:09] ClusterSetupProgressCallback( eSetupPhase = ClusterSetupPhaseFailureCleanup, ePhaseType = ClusterSetupPhaseContinue, ePhaseSeverity = ClusterSetupPhaseInformational, dwPercentComplete = 21, szObjectName = EXCD13, dwStatus = 0x0 )
[2014-01-02T23:29:09] ClusterSetupProgressCallback( eSetupPhase = ClusterSetupPhaseFailureCleanup, ePhaseType = ClusterSetupPhaseEnd, ePhaseSeverity = ClusterSetupPhaseInformational, dwPercentComplete = 21, szObjectName = , dwStatus = 0x0 )

[2014-01-02T23:29:07] The operation wasn't successful because an error was encountered. You may find more details in log file "C:\ExchangeSetupLogs\DagTasks\dagtask_2014-01-02_23-29-02.426_add-databaseavailabiltygroupserver.log".
[2014-01-02T23:29:07] WriteError! Exception = Microsoft.Exchange.Cluster.Replay.DagTaskOperationFailedException: A server-side database availability group administrative operation failed. Error The operation failed. CreateCluster errors may result from incorrectly configured static addresses. Error: Computer account 'EXCD13' couldn't be validated by user 'NT AUTHORITY\SYSTEM'. Error: Unknown error (0xc000018b). ---> Microsoft.Exchange.Cluster.Replay.DagTaskComputerAccountCouldNotBeValidatedException: A server-side database availability group administrative operation failed. Error Computer account 'EXCD13' couldn't be validated by user 'NT AUTHORITY\SYSTEM'. Error: Unknown error (0xc000018b).
   at Microsoft.Exchange.Cluster.ClusApi.AmCluster.CreateExchangeCluster(String clusterName, AmServerName firstNodeName, String[] ipAddress, UInt32[] ipPrefixLength, IClusterSetupProgress setupProgress, IntPtr context, Exception& failureException, Boolean throwExceptionOnFailure)
   at Microsoft.Exchange.Cluster.ClusApi.ClusterFactory.CreateExchangeCluster(String clusterName, AmServerName firstNodeName, String[] ipAddress, UInt32[] ipPrefixLength, IClusterSetupProgress setupProgress, IntPtr context, Exception& failureException, Boolean throwExceptionOnFailure)
   at Microsoft.Exchange.Cluster.Replay.DagHelper.CreateDagCluster(String clusterName, AmServerName firstNodeName, String[] ipAddresses, UInt32[] netmasks, String& verboseLog)
   --- End of inner exception stack trace (Microsoft.Exchange.Cluster.Replay.DagTaskComputerAccountCouldNotBeValidatedException) ---
   at Microsoft.Exchange.Cluster.Replay.DagHelper.ThrowDagTaskOperationWrapper(Exception exception)
   at Microsoft.Exchange.Cluster.Replay.DagHelper.CreateDagCluster(String clusterName, AmServerName firstNodeName, String[] ipAddresses, UInt32[] netmasks, String& verboseLog)
   at Microsoft.Exchange.Cluster.ReplayService.ReplayRpcServer.<>c__DisplayClass40.<RpcsCreateCluster>b__3f()
   at Microsoft.Exchange.Data.Storage.Cluster.HaRpcExceptionWrapperBase`2.RunRpcServerOperation(String databaseName, RpcServerOperation rpcOperation)
   --- End of stack trace on server (EXCMB2.contoso.local) ---
   at Microsoft.Exchange.Data.Storage.Cluster.HaRpcExceptionWrapperBase`2.ClientRethrowIfFailed(String databaseName, String serverName, RpcErrorExceptionInfo errorInfo)
   at Microsoft.Exchange.Cluster.Replay.ReplayRpcClientWrapper.RunCreateCluster(AmServerName rpcServerName, String clusterName, AmServerName firstNode, String[] ipaddrs, UInt32[] netmasks, String& verboseLog)
   at Microsoft.Exchange.Management.SystemConfigurationTasks.AddDatabaseAvailabilityGroupServer.FormCluster()
[2014-01-02T23:29:07] Updated Progress 'Done!' 100%.
[2014-01-02T23:29:07] COMPLETED
add-databaseavailabiltygroupserver explicitly called CloseTempLogFile().

Note: The Windows Firewall is turned off on all Exchange 2013 servers.

I have also disabled all Antivirus services and it made no difference.

Any help will be highly appreciated.

Thank you

Hi PO_IT_Support,

Have you checked the above suggestions I provided?

If there is any update, please feel free to let me know.

Best regards,
Amy

Hi PO_IT_Support,

Have you checked the above suggestions I provided?

If there is any update, please feel free to let me know.

Best regards,

Hi all,

Please be aware I have decided to completely uninstall Exchange 2013, blow away the VM servers and start everything again from scratch.

I'm suspecting this issue could of been something with the Windows Server 2012 Image originally used?

Planning to do a clean install of Windows Server 2012 Standard for all the 2013 Exchange Servers.

Will keep you all updated.

Thank you

Hi all,

Please be aware this issue has been resolved.

We discovered if your running Windows Server 2008 SP2 domain controllers in your environment you will need to install a specific hotfix provided by Microsoft.

Note: This hotfix needs to be installed on your Windows Server 2008 domain controller.

http://support.microsoft.com/kb/976424

Thank you

• Marked as answer by PO_IT_Support Friday, January 17, 2014 11:04 AM
• Edited by PO_IT_Support Thursday, February 20, 2014 12:16 AM

Hi Bisher,

I have updated my answer with the link to the hotfix.

So I am running into a similar issue. However in my case I am running 2008 R2 with SP1. According to the document you do not have to deploy the hotfix if you are running SP1 on your boxes. Also I do not need to run any CNO's because we are deploying our Exchange 2013 boxes on 2012 R2 servers. We are also not needing to input IP address as we are not setting up any Administrative Access Points.

I am able to clearly create the DAG but when I go to add member servers to the DAG, that is when I get the failure of:

" A server-side database availability group administrative operation failed with a transient error. Please try the operation again. Error: An error occurred while attempting a cluster operation. Error: Cluster API failed: "CreateCluster() failed with 0x5. Error: Access is denied""

This message from my searching falls in line with this thread. Every other thread I have seen has been because people were not deploying on 2012 R2 yet and they needed to deploy the Pre-Stage items like CNO's.

Any additional information that might be helpful let me know.

Thank you in advance.

Kris.

I have the same problem...but i have'nt any 2008 servers.

I have a brand new setup with two domain controllers (Server 2012 R2 Standard, fully patched), two Exchange 2013 SP1 servers (Server 2012 R2 standard, fully patched and joined to the domain) and one witness server (Server 2012 R2 Standard, fully patched and joined to the domain)

All these are virtual servers in a clustered SAN.

I have done the setup several times in a lab enviroment without any problems.

The difference between the lab and the final setup is that the lab is a single Hyper-V server with 5 VMs using Hyper-V manager.
And the final setup is 5 VMs in a clustered enviroment using SCVMM.
The VMs have availibility sets so that the Exchange servers will never be on the same host.

I can create the DAG and add ONE Exchange server (doesn't matter wich one i add first), but i get an error when i try to add server number two.

• Proposed as answer by Eirik Jolle Wednesday, December 10, 2014 8:40 PM
• Unproposed as answer by Eirik Jolle Wednesday, December 10, 2014 8:40 PM

I got the same error on a installation of Exchange 2013 DAG just now.

Domain Controllers are Windows 2008R2 and 2012R2.

Witness Server Windows 2008.

I did pre stage the cluster name Object in AD. The DAG where created sucsessfully. But when i tried to add DAG members, I got:

A server-side database availability group administrative operation failed. Error The operation failed. CreateCluster errors may result from incorrectly configured static addresses. Error: Computer account 'EXDAG1' couldn't be validated
by user 'NT AUTHORITY\SYSTEM'. Error: An attempt to use the specified cluster name failed because an enabled computer object with the given name already exists in the domain. [Server: EXSRV1.domain.com]

Turns out i did not disable the DAG Object in AD. Once i disable the cluster name Object in AD, i did not get any error adding DAG member.

• Proposed as answer by Eirik Jolle Wednesday, December 10, 2014 8:40 PM

any update with this issue ?

I do have exact same problem running,  

i do have Domain controllers Server 2008 r2 sp1 and exchange 2013 installed on Server 2012 r2 datacenter