Connecting hosts to the vCenter Server fails with the error : "License not available to perform the operation"

Products

• VMware vCenter Server

Issue/Introduction

• Adding/Re-connecting ESXi host on vCenter Server (VCSA) might return an error :
  License not available to perform the operation. The Evaluation Mode license assigned to "vCenter Server" <vcenter_fqdn> has expired. Recommend updating the license.
  
  
• Refer to the following image for the error displayed in the vCenter Server :
  
  
  
• Errors reported in /var/log/vmware/vpxd/vpxd.log :
  YYYY-MM-DDTHH:MM:SS:###Z error vpxd[#####] [Originator@6876 sub=Default opID=########-###-####-##-##:########-##] [VpxLRO] -- ERROR task-3015 -- ########-####-####-####-############(########-####-####-####-############) -- host-12 -- vim.HostSystem.reconnect: :vmodl.fault.NotEnoughLicenses
--> Result:
--> (vmodl.fault.NotEnoughLicenses) {
-->    faultCause = (vmodl.MethodFault) null,
-->    faultMessage = (vmodl.LocalizableMessage) [
-->       (vmodl.LocalizableMessage) {
-->          key = "com.vmware.vim.vc.license.error.licenseExpired",
-->          arg = (vmodl.KeyAnyValue) [
-->             (vmodl.KeyAnyValue) {
-->                key = "entity",
-->                value = "########-####-####-####-############"
-->             (vmodl.KeyAnyValue) {
-->                key = "entityDisplayName",
-->                value = "<vcenter_fqdn>"
--> (vim.host.ConnectSpec) {
-->    hostName = "<esxi_fqdn>",

Environment

VMware vCenter Server 7.x
VMware vCenter Server 8.x

Cause

This issue is caused due to expired license on vCenter server returning failure for inventory operations.

Resolution

Proceed to add valid license on VCSA using vSphere Client. Refer to : How to Configure License Settings for Your vCenter Server

Additional Information

Retrieve the license for the vCenter Server from the Broadcom support portal using the steps from the KB article : License Key Management for VMware Products

Open a Non-Technical SR with Broadcom, in case the license information is not present in the Broadcom support portal : Create a Non Technical case for Support Portal / License / Contract related issues