Issue

Use this article to troubleshoot a stalled Windows VM, a console white screen, or unavailable RDP.

Environment

• Product: ZCF
• Component: Cloud
• Affected object: Windows VM/console
• Versions: 4.x, 5.x
• Scenario: Windows stall, console white screen, or unavailable RDP

Symptoms

• A Windows VM stalls, its console displays a white screen, or remote desktop login fails, and it might recover after restart.

Possible causes

• Guest OS resources, drivers, patches, the RDP service, memory pressure, or host resource jitter are abnormal.

Resolution

1. First confirm service impact and whether a restart is permitted.
2. Collect VM monitoring data, Windows event logs, a console screenshot, and host resources.
3. Compare with other VMs on the same host to determine whether this is a single-VM or host-wide issue.

Key command

grep -a -nE "<vmUuid>|qemu|libvirt|console|vnc" /usr/local/zstack/apache-tomcat/logs/management-server.log* /var/log/libvirt/qemu/*.log 2>/dev/null

Remediation

• Based on the troubleshooting result, repair the affected component, configuration, data state, or connection path.
• If databases, underlying storage, snapshot chains, VM disks, GPU passthrough, or management-service restarts are involved, first confirm backups, scope of impact, and rollback paths.

Verification

• Confirm that the symptom described in this article no longer occurs.
• UI, API, management-node logs, and underlying command output corroborate one another.
• Observe at least one related task or alarm cycle to confirm that the issue does not recur.

Risks and rollback

• Before remediation in production, confirm customer service impact, the change window, and the rollback plan.
• For data deletion, database modifications, snapshot-chain repairs, underlying file operations, or hardware operations, ZStack recommends contacting technical support for confirmation.

Notes

• For VM startup, migration, HA, Unknown status, or forced stop operations, first confirm the actual VM running location to prevent split-brain operation, dual writes, or unintended service interruption.
• Before adjusting management services, databases, certificates, permissions, auditing, or security settings, confirm the HA state, service window, rollback plan, and compliance-retention requirements.
• If database modifications, underlying file operations, lock release, service restarts, driver or firmware upgrades, or bulk resource changes are required, contact ZStack technical support before proceeding.