Proxmox VE

Startup Errors and Fixes Complete Guide

3 min read

Startup Errors and Fixes Complete Guide

Overview

Complete guide to fixing all VM startup errors. Learn to diagnose and resolve common startup issues quickly.

Error Reference

Error 1: VM Already Running

Message:

vm is already running

Cause:

  • VM started on another node
  • Stale lock file

Fix:

# Check where VM is running
qm list
 
# If running elsewhere, stop there
qm stop 100
 
# Or remove stale lock
rm /var/lib/vz/images/100/lock

Error 2: Storage Not Available

Message:

storage 'local' is not available

Cause:

  • Storage not mounted
  • Storage offline

Fix:

# Check storage
pvesm status
 
# Enable storage
pvesm enable local
 
# Check storage content
pvesm list local

Error 3: Not Enough Disk Space

Message:

no space left on device

Cause:

  • Storage full

Fix:

# Check space
pvesm status
 
# Clean up old backups
rm -rf /var/lib/vz/dump/*
 
# Expand storage
pvesm resize local +10G

Error 4: CPU Not Available

Message:

cpu hotplug failed

Cause:

  • No available CPU cores

Fix:

# Check CPU
pvesh get /nodes/localhost/status
 
# Reduce VM CPU
qm set 100 --cores 2

Error 5: Memory Not Available

Message:

not enough memory

Cause:

  • RAM exhausted

Fix:

# Check memory
free -h
 
# Reduce VM memory
qm set 100 --memory 2048
 
# Enable balloon
qm set 100 --balloon 2048

Error 6: Network Not Available

Message:

network 'vmbr0' does not exist

Cause:

  • Bridge not configured

Fix:

# Check bridges
brctl show
 
# Create bridge
ip link add vmbr0 type bridge
 
# Or use existing
qm set 100 --net0 virtio,bridge=vmbr0

Error 7: Lock Timeout

Message:

could not acquire lock

Cause:

  • Another operation in progress

Fix:

# Check locks
qm list
 
# Wait for lock
sleep 30
 
# Force unlock (dangerous)
qm unlock 100

Error 8: Invalid Configuration

Message:

invalid configuration

Cause:

  • Wrong settings

Fix:

# Check config
qm config 100
 
# Reset to defaults
qm set 100 --memory 2048 --cores 2 --net0 virtio,bridge=vmbr0

Error 9: ISO Not Found

Message:

iso 'local:iso/xxx.iso' does not exist

Cause:

  • ISO not uploaded

Fix:

# List ISOs
pvesm list local
 
# Upload new ISO
pvesm upload local iso/ubuntu.iso
 
# Or remove from config
qm set 100 --ide2 none

Error 10: Permission Denied

Message:

permission check failed

Cause:

  • User lacks permissions

Fix:

# Check ACL
pveum acl list
 
# Grant permission
pveum acl modify /vms/100 --user admin@example.com --role PVEPowerAdmin

Emergency Recovery

Force Start

# Force start
qm start 100 --force 1
 
# Skip lock
qm start 100 --skiplocking 1

Reset Configuration

# Reset VM
qm destroy 100
qm create 100

Prevention

Health Checks

# Pre-boot check
qm start 100 --verify

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