vCenter File-Based Backup fails with "503 Server Error: Service Unavailable for url: http://localhost:1080/wcp"

Products

• VMware vCenter Server
• VMware vCenter Server 7.0

Issue/Introduction

• File-based backup of the vCenter Server Appliance via the Virtual Appliance Management Interface (VAMI) fails with the following errors reported in the /var/log/vmware/applmgmt/backup.log file on vCenter Server:
  
  YYYY-MM-DDTHH:MM:SS ERROR __main__ 1765921 [vc@4413 requestId="######-####-######" processName="ComponentScriptsBackup" module="Log" funcName="run" fileName="Log.py" lineNum="66"] 503 Server Error: Service Unavailable for url: http://localhost:1080/wcp
YYYY-MM-DDTHH:MM:SS ERROR __main__ 1765921 [vc@4413 requestId="YYYY-MM-DDTHH:MM:SS" processName="ComponentScriptsBackup" module="ComponentScripts" funcName="ComponentScriptsBackup" fileName="ComponentScripts.py" lineNum="125"] Component backup command "/etc/vmware/backup/component-scripts/wcp/wcp_backup_restore.py --startBackup" failed 1.
YYYY-MM-DDTHH:MM:SS ERROR __main__ 1765921 [vc@4413 requestId="YYYY-MM-DDTHH:MM:SS" processName="ComponentScriptsBackup" module="ComponentScripts" funcName="ComponentScriptsBackup" fileName="ComponentScripts.py" lineNum="149"] Error during component wcp backup


• 'wcp' service is reported in stopped state along with other required services on vCenter Server: 
  
  service-control --status --all
Running:
 applmgmt lookupsvc lwsmd pschealth vc-ws1a-broker vlcm vmafdd vmcad vmdird vmware-analytics vmware-certificateauthority vmware-certificatemanagement vmware-cis-license vmware-eam vmware-envoy vmware-envoy-hgw vmware-envoy-sidecar vmware-envoy-system-proxy vmware-infraprofile vmware-postgres-archiver vmware-rhttpproxy vmware-stsd vmware-topologysvc vmware-trustmanagement vmware-updatemgr vmware-vapi-endpoint vmware-vdtc vmware-vgfa vmware-vmon vmware-vpostgres vmware-vpxd vmware-vpxd-svcs vmware-vsan-health vmware-vsm vsphere-ui
Stopped:
 fim-agent liagent vc-salt vmcam vmware-content-library vmware-imagebuilder vmware-netdumper vmware-rbd-watchdog vmware-sps vmware-vcha vstats wcp 

Environment

VMware vCenter Server

Cause

During a file-based backup, the vCenter appliance executes component-specific scripts to collect configuration data, including the configurations for the Workload Control Plane (WCP).
This issue occurs if the wcp service, or any of the core services are currently in a stopped state. When the backup framework attempts to query the local WCP endpoint, it fails to connect, receives a 503 Service Unavailable response, and aborts the entire backup job.

Resolution

To resolve this issue, check if all required services are up and running, and start them if they are stopped:

1. Connect to the vCenter Server Appliance via SSH and log in with the root credentials.
2. Check the current status of the vCenter services to verify which services are stopped:
   service-control --status --all
   
   
3. If the critical services are reported in stopped state, then start the services with the following command which are configured to start automatically:
   service-control --start --all
   
   
4. Once the command completes successfully, verify that required services are now in the Running list including wcp service.
5. Return to the vCenter VAMI and trigger the file-based backup again.

Reach out to Broadcom Support if the issue is still not resolved and the backup still fails.