A short script to queue up a start job in proxmox, so that once the FROM vm is fully off, the TO vm is started. It's useful for swapping between GPU passthrough virtual machines without having to use another computer to start the next vm.

switch_vm.sh

#!/bin/bash

FROM=$1
TO=$2

if [ -z "$FROM"  ]; then echo "Usage: ./switch_vm.sh <current_vmid> <next_vmid>"; exit 1; fi
if [ -z "$TO"  ];   then echo "Usage: ./switch_vm.sh <current_vmid> <next_vmid>"; exit 1; fi

echo "waiting for $FROM to shutdown, then starting $TO"
while : ; do

  # read status for starting VM from qemu
  status=$(qm status $FROM)
  echo "$FROM = $status"

  # if the vm reaches a stopped state
  if [[ "$status" == *"stopped"* ]]; then
    # ... start the next VM
    echo "starting $TO..."
    qm start $TO
    echo "started."

    # and exit
    exit 0
  fi
  sleep 1
done