ESX 3.5 host remains in a disconnected state after being added to vCenter Server 4.x or vCenter Server 5.0

Products

• VMware vCenter Server
• VMware vSphere ESXi

Issue/Introduction

Symptoms:

• If you add a ESX 3.5 host to the Inventory in vCenter Server 4.x or vCenter Server 5.0, the host remains in a disconnected state.
• You see the error:
  
  License not available to perform the operation. The license server at [email protected] for vCenter Server xxx.domain.com does not include vCenter agent for ESX Server. Upgrade the licenses on the license server.
  
  
• The License Server is configured correctly with valid applicable licenses.

Environment

VMware ESX Server 3.5.x
VMware vCenter Server 4.1.x
VMware vCenter Server 4.0.x
VMware vCenter Server 5.0.x

Resolution

This issue may occur if the ESX 3.5 host is still connected to the Inventory in a vCenter Server 2.5 instance.

To resolve this issue, you must remove it from the Inventory on the vCenter Server 2.5 instance and add it to the Inventory in vCenter Server 4.x or vCenter Server 5.0.

If your vCenter Server 2.5 instance is no longer available, see Configuring a legacy license server to manage ESX/ESXi 3.x hosts in vCenter Server 4.0 (1010704).

Additional Information

For related information, see Diagnosing an ESX Server that is Disconnected or Not Responding in VirtualCenter (1003409).
Troubleshooting an ESXi/ESX host in non responding state
Configuring a legacy license server to manage ESX/ESXi 3.x hosts in vCenter Server