How to Handle Backup Failures - Complete Guide
Question: My backup failed - how do I fix it?
Answer: Identify and fix the issue
Common Error Messages and Fixes
Error 1: “Storage not available”
Cause: Storage disconnected
Fix:
# Check storage status
pvesm status
# Fix storage
pvesm enable local
# Check storage connectivity
ping storage-server-ipError 2: “No space left on device”
Cause: Storage full
Fix:
# Check storage usage
pvesm status
# Clean old backups
rm /var/lib/vz/dump/vzdump-*.tar.gz
# Configure retention
# Web UI -> Backup -> Job -> Retention -> Set lower valuesError 3: “VM is locked”
Cause: VM in use by another process
Fix:
# Check VM status
qm list
# Wait for process or unlock
qm unlock 100Error 4: “Permission denied”
Cause: User lacks backup permission
Fix:
# Check permissions
pveum acl list
# Grant backup permission
pveum acl modify /vms/100 --user admin@pam --role PVEPowerAdminError 5: “Backup already running”
Cause: Previous backup still running
Fix:
# Wait for completion
# Or kill backup process
pkill vzdumpHow to Debug Backup Issues
Enable Verbose Logging
# Run backup with verbose output
vzdump 100 --mode snapshot --verbose
# Check system logs
tail -f /var/log/pveproxy/access.logHow to Prevent Future Failures
Best Practices
- Monitor storage space weekly
- Set retention properly
- Check logs regularly
- Test restore quarterly
Keywords
troubleshooting error how-to debug