# vi: ts=4 expandtab
#
# Copyright (C) 2014 Canonical Ltd.
#
# Author: Scott Moser <scott.moser@canonical.com>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 3, as
# published by the Free Software Foundation.
#
# This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
"""
**Summary:** reboot system into another init.
**Description:** This module provides a way for the user to boot with systemd
even if the image is set to boot with upstart. It should be run as one of the
first ``cloud_init_modules``, and will switch the init system and then issue a
reboot. The next boot will come up in the target init system and no action will
be taken.
This should be inert on non-ubuntu systems, and also exit quickly.
It can be configured with the following option structure::
init_switch:
target: systemd (can be 'systemd' or 'upstart')
reboot: true (reboot if a change was made, or false to not reboot)
.. note::
Best effort is made, but it's possible
this system will break, and probably won't interact well with any other
mechanism you've used to switch the init system.
"""
from cloudinit.distros import ubuntu
from cloudinit import log as logging
from cloudinit.settings import PER_INSTANCE
from cloudinit import util
import os
import time
frequency = PER_INSTANCE
REBOOT_CMD = ["/sbin/reboot", "--force"]
DEFAULT_CONFIG = {
'init_switch': {'target': None, 'reboot': True}
}
SWITCH_INIT = """
#!/bin/sh
# switch_init: [upstart | systemd]
is_systemd() {
[ "$(dpkg-divert --listpackage /sbin/init)" = "systemd-sysv" ]
}
debug() { echo "$@" 1>&2; }
fail() { echo "$@" 1>&2; exit 1; }
if [ "$1" = "systemd" ]; then
if is_systemd; then
debug "already systemd, nothing to do"
else
[ -f /lib/systemd/systemd ] || fail "no systemd available";
dpkg-divert --package systemd-sysv --divert /sbin/init.diverted \\
--rename /sbin/init
fi
[ -f /sbin/init ] || ln /lib/systemd/systemd /sbin/init
elif [ "$1" = "upstart" ]; then
if is_systemd; then
rm -f /sbin/init
dpkg-divert --package systemd-sysv --rename --remove /sbin/init
else
debug "already upstart, nothing to do."
fi
else
fail "Error. expect 'upstart' or 'systemd'"
fi
"""
[docs]def handle(name, cfg, cloud, log, args):
"""Handler method activated by cloud-init."""
if not isinstance(cloud.distro, ubuntu.Distro):
log.debug("%s: distro is '%s', not ubuntu. returning",
name, cloud.distro.__class__)
return
cfg = util.mergemanydict([cfg, DEFAULT_CONFIG])
target = cfg['init_switch']['target']
reboot = cfg['init_switch']['reboot']
if len(args) != 0:
target = args[0]
if len(args) > 1:
reboot = util.is_true(args[1])
if not target:
log.debug("%s: target=%s. nothing to do", name, target)
return
if not util.which('dpkg'):
log.warn("%s: 'dpkg' not available. Assuming not ubuntu", name)
return
supported = ('upstart', 'systemd')
if target not in supported:
log.warn("%s: target set to %s, expected one of: %s",
name, target, str(supported))
if os.path.exists("/run/systemd/system"):
current = "systemd"
else:
current = "upstart"
if current == target:
log.debug("%s: current = target = %s. nothing to do", name, target)
return
try:
util.subp(['sh', '-s', target], data=SWITCH_INIT)
except util.ProcessExecutionError as e:
log.warn("%s: Failed to switch to init '%s'. %s", name, target, e)
return
if util.is_false(reboot):
log.info("%s: switched '%s' to '%s'. reboot=false, not rebooting.",
name, current, target)
return
try:
log.warn("%s: switched '%s' to '%s'. rebooting.",
name, current, target)
logging.flushLoggers(log)
_fire_reboot(log, wait_attempts=4, initial_sleep=4)
except Exception as e:
util.logexc(log, "Requested reboot did not happen!")
raise
def _fire_reboot(log, wait_attempts=6, initial_sleep=1, backoff=2):
util.subp(REBOOT_CMD)
start = time.time()
wait_time = initial_sleep
for _i in range(0, wait_attempts):
time.sleep(wait_time)
wait_time *= backoff
elapsed = time.time() - start
log.debug("Rebooted, but still running after %s seconds", int(elapsed))
# If we got here, not good
elapsed = time.time() - start
raise RuntimeError(("Reboot did not happen"
" after %s seconds!") % (int(elapsed)))