mm1ke / qemu-init

QEmu/KVM init script for gentoo

qemu-init

This repository contains scripts for starting, stopping and manipulation qemu virtual machines.

Motivation

Initially i've wrote this script in order to have a openrc init script to start and stop virtual machines without the the need to depend on app-emulation/libvirt. However, as I started to play more with virtual machines directly (and not as an system service), i've decided to create qvm which is a simple tool to work with virtual machines directly.
The init script still require qvm to be present for starting and stopping vm's as a service, but qvm can be used as a standalone tool perfectly well.

qvm (qemu vm manager)

This is a bash script for managing qemu virtual machines. Features include:

• start / stop / reset / freeze qemu virtual machines
• modify guests
  • set vnc/spice password
  • change memory (ballooning)
  • send key strokes
• modify guests hardware
  • add / remove pcie devices (network adapters and/or hard-disks)
  • list connected pcie devices
• guest snapshoting
  • create / remove snapshots
  • list available snapshots
  • load snapshots as needed
• host network
  • add / remove tap interfaces on the host

Dependencies

qvm require to have following tools installed:

• app-emulation/qemu
• net-misc/bridge-utils
• net-analyzer/openbsd-netcat or net-misc/socat
• sys-apps/iproute2

qvm-completion.bash

qvm comes with a nice bash completion too.

kvm.init & kvm.confd

kvm.init is the openrc init script. This can be used to create system services to start virtual machines via openrc. kvm.init requires qvm in order to start and stop virtual machines.
kvm.confd is the default configuration file for the kvm.init script.

default.config

There is also a default.config included which can be used as an example configuration for new virtual machines. Configuration files are usually put into /etc/qvm/. However the path can be changed (see below).

Installation

qvm

In order to use qvm, simply put it into /usr/bin/. The completion should be put into /usr/share/bash-completionk/completions/ (on a gentoo box). qvm first checks if there is a ~/.config/qvm/qvm.conf which it would source if available. In this file you can set the default configuration path for virtual machines, as well as other settings:

cp qvm /usr/bin/
chmod +x /usr/bin/qvm

Create a new configuration file:

touch ~/.config/qvm/qvm.conf

• CFG_DIR="~/vmcfg" set's the default path for vm configuration files
• VM_KILL_WAIT="20" set's the default time to wait until a vm should be killed (after initiating a shutdown)
• TAP_DELETE=false defines if created TAP devices should be removed from the host when a vm shut down.

qvm usually doesn't need any root privileges. However this also depends on the VM config. For example, TAP devices require root privileges to be created, which qvm kindly would ask for.
The default.config work with bridge devices, which itself are TAP devices again but are handled by qemu directly. Here it's once required to allow qemu for which bridge devices it can create tap devices for. This can be configured in /etc/qemu/bridge.conf. After that users can create/delete TAP devices without root privileges.

If qvm is run as root user it also looks for an configuration in the root's home directory. In the absence of the configuration file it tries to use the default config directory under /etc/qvm - were config files of service vm's should be put to.

init scripts

If you're using the openrc init system and want to start vms as a service simply put kvm.init into /etc/init.d/ and symlink vms to it. configuration files need to be installed in CONF_PATH (default is /etc/qvm/), or can be set in /etc/conf.d/kvm. For example:

cp kvm.init /etc/init.d/
cp kvm.confd /etc/conf.d/kvm

Note that qvm is required to be installed.

To add a new vm as a service:

cp default.config /etc/qvm/kvm.gentoo
cd /etc/init.d/
ln -s kvm.init kvm.gentoo

License

All scripts are free software. You can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.