Enabling vLCM fails on NSX enabled cluster fails with error "Error occurred while checking whether NSX-T Data Center is enabled on this cluster"

Products

• VMware NSX

Issue/Introduction

• When trying to enable vLCM cluster is failing with the error message "A general system error occurred: Error occurred while checking whether NSX-T Data Center is enabled on this cluster."
  
• In the VMware vCenter Update Update Manager logs (/var/log/vmware/vmware-updatemgr/vum-server/vmware-vum-server.log)
  
  2025-07-07T11:23:59.847Z warning vmware-vum-server[08494] [Originator@6876 sub=IO.Connection] Failed to connect; <io_obj p:0x00007f976c243af0, h:28, <TCP '#.#.#.# : 40830'>, <TCP '#.#.#.# : 443'>
>, e: 110(Connection timed out), duration: 129314msec
2025-07-07T11:23:59.847Z warning vmware-vum-server[08494] [Originator@6876 sub=HttpConnectionPool-000000] Failed to get pooled connection; <cs p:00007f973809fbc0, TCP:#.#.#.#:443>, (null), duration: 1
29315msec, N7Vmacore15SystemExceptionE(Connection timed out)
--> [context]#######################################################################################################################################################/6D2xpYmMuc28uNgA=[/context]
2025-07-07T11:23:59.848Z info vmware-vum-server[08494] [Originator@6876 sub=IO.Http] Set user agent error; state: 1, (null), N7Vmacore15SystemExceptionE(Connection timed out)
--> [context]#######################################################################################################################################################/6D2xpYmMuc28uNgA=[/context]
2025-07-07T11:23:59.849Z error vmware-vum-server[2177287] [Originator@6876 sub=com.vmware.vcIntegrity.lifecycle.CheckFeatureApplicabilityTask] [Task, 524] Task:com.vmware.vcIntegrity.lifecycle.CheckFeatur
eApplicabilityTask ID:########-####-####-####-9a62eddff303. Failed to check whether nsx-t is enabled on 'domain-####(######)' cluster. Error: Connection timed out
2025-07-07T11:23:59.849Z info vmware-vum-server[2177287] [Originator@6876 sub=com.vmware.vcIntegrity.lifecycle.CheckFeatureApplicabilityTask] [Task, 524] Task:com.vmware.vcIntegrity.lifecycle.CheckFeature
ApplicabilityTask ID:########-####-####-####-9a62eddff303. Finalizing Task
2025-07-07T11:23:59.849Z error vmware-vum-server[2177287] [Originator@6876 sub=com.vmware.vcIntegrity.lifecycle.CheckFeatureApplicabilityTask] [Task, 524] Task:com.vmware.vcIntegrity.lifecycle.CheckFeatur
eApplicabilityTask ID:########-####-####-####-9a62eddff303. Task Failed. Error: Error:
-->    com.vmware.vapi.std.errors.error
--> Messages:
-->    com.vmware.vcIntegrity.lifecycle.enablement.NsxtCheck.Failure<Error occurred while checking whether NSX-T Data Center is enabled on this cluster.>
-->
  
  
• The following error may also be observed
  2025-07-03T15:30:27.206Z error vmware-vum-server [2716556] [Originator@6876 sub=com. vmware. vcIntegrity. lifecycle. CheckFeatureApplicabilityTask] [Task, 524] Task:com.vmwar.vcIntegrity. lifecycle. CheckFeatureApplicabilityTask ID: ########-####-####-####-41ed53bf84d8. Failed to check whether nsx-t is enabled on 'domain-### (#######) ' cluster.Error: Host not found (authoritative) : The connection was closed by the remote end during handshake.
  
  

Environment

VMware NSX-T Datacenter 
VMware NSX-T

Cause

• This issue is due to communication issues between vCenter and NSX manager VIP/NSX managers.
• An incorrect DNS PTR can also contribute to this error.

Resolution

• SSH into the VCSA to test connectivity to the remote NSX Manager's URL over TCP 443 which a required port to opened. There should be a clear indication of a successful SSL/HTTP session. If not, engage your firewall team .
  curl -k -v https://<NSX_MANGER_FQDN>
curl -k -v https://<NSX_MANGER_VIP_FQDN>
  
  
• Run the command "nslookup" against NSX-MGR VIP to confirm if DNS PTR is accurate. If it is not, contact the DNS administrator to find and remove the incorrect PTR.
  nslookup <NSX-MGR VIP>