ansible/virt_boot

310 lines
10 KiB
Text
Raw Normal View History

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# (c) 2012, Jeroen Hoekx <jeroen@hoekx.be>
#
# This file is part of Ansible
#
# Ansible is 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 3 of the License, or
# (at your option) any later version.
#
# Ansible is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible. If not, see <http://www.gnu.org/licenses/>.
DOCUMENTATION = '''
---
author: Jeroen Hoekx
module: virt_boot
short_description: Define libvirt boot parameters
description:
- "This module configures the boot order or boot media of a libvirt virtual
machine. A guest can be configured to boot from network, hard disk, floppy,
cdrom or a direct kernel boot. Specific media can be attached for cdrom,
floppy and direct kernel boot."
- This module requires the libvirt module.
version_added: "0.8"
options:
domain:
description:
- The name of the libvirt domain.
required: true
boot:
description:
- "Specify the boot order of the virtual machine. This is a comma-separated
list of: I(fd), I(hd), I(cdrom) and I(network)."
required: false
bootmenu:
description:
- Enable or disable the boot menu.
required: false
choices: [ "yes", "no" ]
kernel:
description:
- The path of the kernel to boot.
required: false
initrd:
description:
- The path of the initrd to boot.
required: false
cmdline:
description:
- The command line to boot the kernel with.
required: false
device:
default: hdc
description:
- The libvirt device name of the cdrom/floppy.
required: false
image:
description:
- The image to connect to the cdrom/floppy device.
required: false
examples:
- description: Boot from a cdrom image.
code: virt_boot domain=archrear image=/srv/rear/archrear/rear-archrear.iso boot=cdrom
- description: Boot from the local disk.
code: virt_boot domain=archrear boot=hd
- description: Boot a specific kernel with a special command line.
code: virt_boot domain=archrear kernel=$storage/kernel-archrear initrd=$storage/initramfs-archrear.img cmdline="root=/dev/ram0 vga=normal rw"
- description: Boot from the harddisk and if that fails from the network.
code: virt_boot domain=archrear boot=hd,network
- description: Enable the boot menu.
code: virt_boot domain=archrear bootmenu=yes
requirements: [ "libvirt" ]
notes:
- Run this on the libvirt host.
- I(kernel) and I(boot) are mutually exclusive.
- This module can not change a running system.
- Using direct kernel boot will always result in a I(changed) state due to libvirt internals.
'''
from xml.dom.minidom import parseString
try:
import libvirt
except ImportError:
print "failed=True msg='libvirt python module unavailable'"
sys.exit(1)
def get_domain(name):
conn = libvirt.open("qemu:///system")
domain = conn.lookupByName(name)
return domain, conn
def get_xml(domain):
domain_data = domain.XMLDesc(libvirt.VIR_DOMAIN_XML_INACTIVE)
tree = parseString(domain_data)
return tree
def write_xml(tree, conn):
conn.defineXML( tree.toxml() )
def element_text(element, data=None):
if data:
to_be_removed = []
for node in element.childNodes:
to_be_removed.append(node)
for node in to_be_removed:
element.removeChild(node)
element.appendChild( element.ownerDocument.createTextNode(data) )
if element.firstChild and element.firstChild.nodeType==element.TEXT_NODE:
return element.firstChild.data
def get_disk(tree, device):
for target in tree.getElementsByTagName('target'):
if target.getAttribute("dev") == device:
return target
def attach_disk(domain, tree, device, image):
disk = get_disk(tree, device)
if disk:
source = disk.parentNode.getElementsByTagName('source').item(0)
if source and source.getAttribute("file") == image:
return False
CDROM_TEMPLATE='''<disk type="file" device="disk">
<driver name="qemu" type="raw"/>
<source file="{path}"/>
<target bus="virtio" dev="{dev}"/>
</disk>'''
xml = CDROM_TEMPLATE.format(path=image, dev=device)
domain.updateDeviceFlags(xml, libvirt.VIR_DOMAIN_AFFECT_CONFIG)
return True
def detach_disk(domain, tree, device):
disk = get_disk(tree, device)
if disk:
source = disk.parentNode.getElementsByTagName('source').item(0)
if source and source.hasAttribute("file"):
source.removeAttribute("file")
xml = disk.parentNode.toxml()
domain.updateDeviceFlags(xml, libvirt.VIR_DOMAIN_AFFECT_CONFIG)
return True
return False
def main():
module = AnsibleModule(
argument_spec = dict(
domain=dict(required=True, aliases=['guest']),
boot=dict(),
bootmenu=dict(choices=BOOLEANS),
kernel=dict(),
initrd=dict(),
cmdline=dict(),
device=dict(default='hdc'),
image=dict(),
),
required_one_of = [['boot','kernel','image','bootmenu']],
mutually_exclusive = [['boot','kernel']]
)
params = module.params
domain_name = params['domain']
boot = params['boot']
bootmenu = module.boolean(params['bootmenu'])
kernel = params['kernel']
initrd = params['initrd']
cmdline = params['cmdline']
device = params['device']
image = params['image']
changed = False
domain, conn = get_domain(domain_name)
if domain.isActive():
module.fail_json(msg="Domain %s is still running."%(domain_name))
tree = get_xml(domain)
### Connect image
if image:
changed = changed or attach_disk(domain, tree, device, image)
if not boot and not kernel:
module.exit_json(changed=changed, image=image, device=device)
else:
changed = changed or detach_disk(domain, tree, device)
if changed:
tree = get_xml(domain)
### Boot ordering
os = tree.getElementsByTagName('os').item(0)
boot_list = os.getElementsByTagName('boot')
kernel_el = os.getElementsByTagName('kernel').item(0)
initrd_el = os.getElementsByTagName('initrd').item(0)
cmdline_el = os.getElementsByTagName('cmdline').item(0)
if boot:
if kernel_el:
changed = True
kernel_el.parentNode.removeChild(kernel_el)
if initrd_el:
changed = True
initrd_el.parentNode.removeChild(initrd_el)
if cmdline_el:
changed = True
cmdline_el.parentNode.removeChild(cmdline_el)
items = boot.split(',')
if boot_list:
needs_change = False
if len(items) == len(boot_list):
for (boot_el, dev) in zip(boot_list, items):
if boot_el.getAttribute('dev') != dev:
needs_change = True
else:
needs_change = True
if needs_change:
changed = True
to_be_removed = []
for boot_el in boot_list:
to_be_removed.append(boot_el)
for boot_el in to_be_removed:
os.removeChild(boot_el)
for item in items:
boot_el = tree.createElement('boot')
boot_el.setAttribute('dev', item)
os.appendChild(boot_el)
else:
changed = True
for item in items:
boot_el = tree.createElement('boot')
boot_el.setAttribute('dev', item)
os.appendChild(boot_el)
elif kernel:
if boot_list:
changed = True
to_be_removed = []
for boot_el in boot_list:
to_be_removed.append(boot_el)
for boot_el in to_be_removed:
os.removeChild(boot_el)
if kernel_el:
if element_text(kernel_el) != kernel:
changed = True
element_text(kernel_el, kernel)
else:
changed = True
kernel_el = tree.createElement('kernel')
kernel_el.appendChild( tree.createTextNode(kernel) )
os.appendChild(kernel_el)
if initrd_el:
if element_text(initrd_el) != initrd:
changed = True
element_text(initrd_el, initrd)
else:
changed = True
initrd_el = tree.createElement('initrd')
initrd_el.appendChild( tree.createTextNode(initrd) )
os.appendChild(initrd_el)
if cmdline_el:
if element_text(cmdline_el) != cmdline:
changed = True
element_text(cmdline_el, cmdline)
else:
changed = True
cmdline_el = tree.createElement('cmdline')
cmdline_el.appendChild( tree.createTextNode(cmdline) )
os.appendChild(cmdline_el)
### Enable/disable bootmenu
bootmenu_state = tree.getElementsByTagName('bootmenu').item(0)
if bootmenu and bootmenu_state:
bootmenu_enabled = bootmenu_state.getAttribute('enable')
if bootmenu_enabled != 'yes':
changed = True
bootmenu_state.setAttribute('enable', 'yes')
elif bootmenu:
os = tree.getElementsByTagName('os').item(0)
bootmenu_state = tree.createElement('bootmenu')
bootmenu_state.setAttribute('enable', 'yes')
changed = True
os.appendChild(bootmenu_state)
elif bootmenu_state:
bootmenu_state.parentNode.removeChild(bootmenu_state)
changed = True
### save back
write_xml(tree, conn)
module.exit_json(changed=changed)
# this is magic, see lib/ansible/module_common.py
#<<INCLUDE_ANSIBLE_MODULE_COMMON>>
main()