VMware ESX Server Disconnected form vCenter Server 

ESX Server was disconnected form the VCenter Server and while trying to reconnect it through vSphere client, following error occurred.

Error:

A general system error occurred: internal error: vmodl.fault.HostCommunication.

Solution:

Restart the ESX server Management Service.
Login to that particular ESX server through console or remote SSH session and execute the following comment.
#service mgmt-vmware restart
Now you can try reconnecting the server to Virtual Center server.
*If the above solution is not solving the problem, Check whether the name resolution is configured correctly.