Backup Exec 2010 Exchange 2010 DAG - Can't connect to agent on DAG members - sudden change

[neigsti]

Greetings

Backup Platform
BackupExec 2010 / Windows 2003R2/x64

Exchange Platform
1 CAS - Exchange 2010 (v14 Build 639.21) / Windows 2008R2x64
2 DAG member servers w/ identical replicated stores - Exchange 2010 (v14 Build 639.21) / Windows 2008R2x64

Symptoms: Backup and communications between BE2010 and the DAG had been working for 2 months until Monday (August 2, 2010) when Hotfix 351400 was installed from live update.  Now when the backup job is started the following error message is supplied: "The media server could not connect to the remote computer.  The remote computer may not be running the Backup Exec Remote Agent for Windows/Linux.  Make sure that the correct version of the Remote Agent is installed and running on the target computer."

Attempted resolutions: 1. Restarted DAG member servers. 2. Pushed out remote agent updates from BE2010 console.  The first time one update was applied and the DAG servers were rebooted.  3. Pushed out remote agents again but no updates were applied this time.  4. Tried to update selections under Job Setup.  The console sees the DAG under Exchange Database Availability Groups.  However, after expanding the DAG the following Error message is present: "The media server could not connect to the Exchange 2010 DAG virtual node."  The message goes on to suggest that I right click on the virtual node icon, click properties and ensure the correct version of the remote agent is installed and running which I am not able to do.

Observations: On the Remote Agent Utility running on the DAG member servers under the Publishing tabs only one entry is listed under "Published names for this agent" which is the server name.  However, previously under the non-hotfixed agent both the server name and the dag FQDN appeared (for example, both: server.organization.com and dag1.organization.com were listed). 

Not sure how to further troubleshoot this one but at least a topic is out there incase others run across the same problem.  I will contact Symantec support in the morning and will try to post any resolution here if available.  It looks suspiciously like the hotfix caused a conduit to fail - so much for being an early adopter.  Thanks in advance for any suggestions or ideas.  Take care

[RahulG]

Silly question , But are you able to ping the virtual node ?
Performt he following steps

1. From the Media Server, Ping the IP address of the Cluster. If a fail with timeout occurs, proceed to the next step.

2. On the active Exchange node, open the Failover Cluster Manager.

3. Check the Cluster network name section. The Cluster Name and IP address must be in an "Online" state.

4. If the Cluster Name or IP address is in an "Offline" state it is recommended to contact Microsoft support to further troubleshoot the issue.

[RahulG · Accepted solution]

refer the following document as well http://support.veritas.com/docs/352105

[neigsti]

You called it!  Now I get to learn about Failover Clustering since I am just the backup guy and the Windows Admin is on vacation.

[neigsti]

Got the DAG back up and running and for the benefit of others who have an Exchange DAG group that goes unresponsive (We were able to move mounted volumes between members servers but the DAG was not responding to pings or applications like BE) a server admin used the following as a solution:

Magic checkbox:
http://www.ntweekly.com/?p=558
 
Registry Key:
http://social.technet.microsoft.com/Forums/en-US/winserverClustering/thread/743d6698-fc4a-4e55-95f0...

Hope this helps others