the networkmanager has not yet been initialized

I faced a very strange case with Exchange DAG, I was doing a site resiliency test I failed over to the DR site successfully and then I failed back to the main site, after failing back I found that the DAG was in a state that looks like split brain syndrome although the DAG was running in DAC mode.

the symptoms were as follows:

From the DR mailbox server:

• Cluster Console only showed this node while the active nodes were not present.
• From EMC the copies on the DR server were healthy.

From the Main site mailbox servers:

• Cluster console showed the three nodes but the DR node was stopped, and the option to start it was grayed out.
• From EMC the copies on the DR server were failed.

The fix was as follows:

•  run the following command: Cluster     /forcecleanup

Then run the following: Start-DatabaseAvailabilityGroup "DAGname" -MailboxServer  "DRNodeName"

After the first command you will find that the DR node can see the other nodes in the cluster console, but the DR node will be stopped, so run the second command to start it.

 

That's It !