A virtual machine cannot be powered on and shows as unknown

Products

• VMware vCenter Server
• VMware vSphere ESXi

Issue/Introduction

Symptoms:

• A virtual machine cannot be powered on and shows as unknown in VirtualCenter.
• A virtual machine shows as unknown when connected directly to an ESX host via VMware Infrastructure (VI) Client.
• The virtual machine World ID is still running.

Environment

VMware ESX Server 3.5.x
VMware VirtualCenter 2.5.x

Resolution

To resolve this issue, you must delete files in /var/lib/vmware/hostd/stats.

Note: Before you begin, see Restarting the Management agents on an ESX Server (1003490) for important information on restarting the mgmt-vmware service.

1. Log in as root to the ESX host with an SSH client.
2. Change the directory to:
   
   cd /var/lib/vmware/hostd/stats
   
   
3. There are four files in this directory. To confirm, perform a directory listing with the command:
   
   ls
   
   
4. Remove these files with the command:
   
   rm *
   
   
5. Restart the Management agents. For more information, see Restarting the Management agents on an ESX Server (1003490).

If the preceding steps do not resolve the issue, see:

• Virtual machines appear as unknown in inventory on host and invalid in vCenter Server (1031605)
• Inaccessible virtual machines are named as Unknown VM (2172)

Additional Information

Virtual machines appear as unknown in Inventory on host and invalid in vCenter Server
仮想マシンをパワーオンできず、不明として表示される
虚拟机无法打开电源并显示为“未知”
Inaccessible virtual machines are named as Unknown VM