ESXi upgrade fails at ESX UPGRADE VUM STAGE POSTCHECK with unknown error in SDDC Manager

Products

• VMware Cloud Foundation

Issue/Introduction

Symptoms:

• ESXi upgrade fails at the ESX UPGRADE VUM STAGE POSTCHECK stage in SDDC Manager.
• The following errors may be observed in the /var/log/vmware/vcf/lcm/lcm-debug.log file:

2025-04-03T15:58:45.932-0600 ERROR [vcf_lcm,67ef0495dddfd9a144011b107e3e1f2d,20d6] [c.v.evo.sddc.lcm.model.task.SubTask,http-nio-127.0.0.1-7400-exec-2] Upgrade error occurred:
The ESXi update postcheck failed with an unknown error.
Reference token <token_id>

2025-04-03T15:59:15.473-0600 INFO  [vcf_lcm,67ef04b38baa193083f2d71e0b2d930c,b083] [c.v.e.sddc.lcm.audit.AuditScheduler,vac-scheduler-1] Last upgrade status for software type ESX_HOST and resourceId <host-id> is: {"id":"373","bundleId":"7a70a555-74ec-4849-89d4-3e45b551c8d8","bundleElementId":"435b7342-9ec6-4692-8ca8-dcc396633313","bundleElementOrder":1,"resourceType":"ESX_HOST","resourceId":"<host-id>","upgradeId":"0c99f3b1-1aff-4b5c-b9c5-c24355906372","upgradeStatus":"COMPLETED_WITH_FAILURE","upgradeError":

{"errorType":"RECOVERABLE","stage":"ESX_UPGRADE_VUM_STAGE_POSTCHECK","errorCode":"ESX_UPGRADE_VUM_POSTCHECK_FAILED_UNKNOWN_ERROR","errorDescription":"\nThe ESXi update postcheck failed with an unknown error.","errorDescriptionCodes":["ESX_UPGRADE_VUM_POSTCHECK_FAILED_UNKNOWN_ERROR"],"errorDescriptionAttributes":{"0":"Existing SSH key not found for host <host-fqdn>"},"metadata":"\nManual intervention needed as upgrade failed during install stage.\nCheck for errors in the lcm log files located on SDDC Manager under /var/log/vmware/vcf/lcm.\n Please retry the upgrade once the upgrade is available again."

Cause

During the host commission process (in VCF), the host DNS name gets normalized to lowercase while persisting the information.

Resolution

To resolve the issue, please follow the steps below:

1. Replace the problematic hostname(s) in the known_hosts files at the locations below with the hostname(s) in lower case:

/root/.ssh/known_hosts
/home/vcf/.ssh/known_hosts
/etc/vmware/vcf/commonsvcs/known_hosts

2. Restart all SDDC Manager services:

systemctl restart domainmanager
systemctl restart operationsmanager
systemctl restart commonsvcs
systemctl restart lcm

Note: This command will restart all SDDC Manager services:
/opt/vmware/vcf/operationsmanager/scripts/cli/sddcmanager_restart_services.sh