HC machine showing Down or not activated due to communication issue

Question: Server status showing down and receiving error Error: 73400260: Unknown exception occurred while communicating with Remote Server in the Cluster?

In the HC cluster machine showing Not Activated and license page is not pulling complete information

Please ensure the following:

    1. If you are running multiple machines in HC cluster then make sure you are running same build of Hosting Controller on all these servers.

    2. Network card which holds HC panel IP address must have top priority (This case only applies in case you have multiple network cards on the machine).

    To set priority of the network card go to Start :: Run :: Control Panel :: Network Card :: Advanced tab :: Advanced Setting. Bring NIC card on top list to set high priority.

    3. If firewall is configured among servers then following ports must remain open for incoming/outgoing TCP/IP request on all severs:

    SQL port = 1433
    HC Server port = 8788
    HC Remoting port = 8789

    4. Go to Services Management Console by clicking Start :: Run :: services.msc. Press Enter and restart the HC Remoting service on all the servers showing as down.

    5. In case IIS is installed on the machine then recycle HCAppPool from Start :: Run :: inetmgr :: IIS :: Application Pool (This would refresh all HC panel web related services).

    6. Follow this last step only in case you have changed the Server IP address, as this effect communication between server and HC database server. In order to resolve this issue, consult with this

7- In some cases where Server status showing UP but License show in active, and when you click on Edit Server it take long time to load the page. Such issue been noticed with HC remote (subsequent) machines which are running in HyperV environment. To fix that case please follow additional steps below
  • Go to HC installation directory C:\Program Files\Advanced Communications\HostingController\Services, take backup of file CAO.Config
  • Edit CAO.Config file in NotePad and check at bottom for entry like " <channel ref="tcp" port="8788"> "
  • Replace that entry with <channel ref="tcp" port="8788" bindTo="IPAddress"> 
    Note: Replace IPAddress = With Original IP of the same machine which display in the HC Panel i.e
  • Restart HCRemoting Service