While upgrading ESXi host using vLCM, we receive the error "VMware vSphere Lifecycle Manager had an unknown error. Check the events and log files for details"

Products

• VMware vSphere ESXi

Issue/Introduction

• Issue happens when scanning for upgrade and not for patching.
• At the time of the issue, we see below errors in /var/log/vmware/vmware-updatemgr/vum-server/vmware-vum-server.log 

YYYY-MM-DDT17:59:22.097Z info vmware-vum-server[72658] [Originator@6876 sub=Activation] [activationValidator 370] Leave Validate. Succeeded for integrity.VUMTaskManager.getVUMTaskInfo on target: Integrity.VUMTaskManager
YYYY-MM-DDT17:59:22.098Z warning vmware-vum-server[72658] [Originator@6876 sub=VUMTaskManagerImpl] [VUMTaskManagerImpl 139] No TaskInfo for vim.Task:task-755953
YYYY-MM-DDT17:59:24.383Z warning vmware-vum-server[2406165] [Originator@6876 sub=IO.Connection] Failed to connect; <io_obj p:0x00007f1c1c11c3a0, h:26, <TCP '"vCenter IP" : 45362'>, <TCP '"Host IP" : 80'>>, e: 110(Connection timed out), duration: 130589msec
YYYY-MM-DDT17:59:24.383Z warning vmware-vum-server[2406165] [Originator@6876 sub=HttpConnectionPool-000000] Failed to get pooled connection; <cs p:00007f1c7c4cad40, TCP:"Host FDQN" :80>, (null), duration: 130590msec, N7Vmacore15SystemExceptionE(Connection timed out)

• At the ESXi host level from /var/log/vua.log see the VUA agent is being started for the scan and later it is disabled again as no incoming request. 

YYYY-MM-DDT17:57:11.764Z - time the service was last started 2025-04-07T17:57:11.755Z, Section for VMware vSphere Update Manager Agent, pid=2103939, version=8.0.3, build=24322831, option=Release


Environment

vSphere 8.x

 

Cause

Network connectivity issues between ESXi hosts and vCenter Server. The connection to TCP 80 ingoing on the host is blocked. 

 

Resolution

Resolve the communication between host and vCenter on port 80 (incoming to the ESXi host)

Additional Information

Refer following kb for testing the basic communication and DNS between ESXi host and vCenter https://knowledge.broadcom.com/external/article/386451/