To manage ESX/ESXi hosts using vCenter Server, you must add the hosts to the vSphere environment through the vSphere Client.

When you add a host, vCenter Server discovers and adds all the virtual machines contained within that managed host to the environment.

Before you begin this task:

Ensure a communication channel through a firewall, if needed. If any managed host in the vCenter Server environment is behind a firewall, ensure that the managed host can communicate with vCenter Server and with all other hosts. See the ESX Server Configuration Guide or the ESXi Server Configuration Guide for information on which ports are necessary.

Make sure NFS mounts are active. If NFS mounts are unresponsive, the operation fails.


If you are connecting your vSphere Client to an ESX/ESXi host directly, the tasks in this section do not apply.