MSExchangeGuru.com

Today I was in a situation where my system admin restarted the Hyper-V which had my DAG nodes and FSW servers.

 

Environment and Overview of the issue:

In this environment I have 2 DAG nodes and one FSW server.

Restart of the HyperV crashed one of my node and assigned a new IP to FSW Server.

Now I am into 2 issues. One my DAG is down and second Node has crashed.

My priority to bring the DAG up and running with at least one node.

Over All I got 3 Issues here

 

Issue 1:

DAG is down and no one can access mailboxes.

 

Troubleshooting:

-Ran the command Get-DatabaseAvailabilityGroup –status | FL and got the following error

===============================================================================================================================

WARNING: An unexpected error has occurred and a Watson dump is being generated: Object reference not set to an instance of an object.

Object reference not set to an instance of an object.

+ CategoryInfo : NotSpecified: (:) [Get-DatabaseAvailabilityGroup], NullReferenceException

+ FullyQualifiedErrorId : System.NullReferenceException,Microsoft.Exchange.Management.SystemConfigurationTasks.Get DatabaseAvailabilityGroup

+ PSComputerName : 2013vtc1.vtc2013.edu

===============================================================================================================================

 

-Checked the Failover cluster but neither I was able to connect to the cluster nor validate it.

-Checked DNS Cluster’s DNS entry was missing and FSW Entry was old IP.

 

Resolution 1:

Changed the FSW server’s new IP and restarted Cluster Service. DAG came up with one Dag node.

Also created DAG host record in the DNS with the checkbox “Allow any authenticated user to update DNS records with the same owner name” which will allow DAG to update the DNS entry.

 

Part 2 is available here: https://msexchangeguru.com/2014/02/05/e2013-dr-dag-post-crash2/

 

Prabhat Nigam

Microsoft MVP | Exchange Server

Team@MSExchangeGuru

Posted February 5th, 2014 under Clustering, DAG, Database Management, Disaster Recovery, Exchange 2010, Exchange 2013. RSS 2.0 feed. Leave a response, or trackback.