pvc/node-daemon/pvcnoded/VMInstance.py

762 lines
34 KiB
Python

#!/usr/bin/env python3
# VMInstance.py - Class implementing a PVC virtual machine in pvcnoded
# Part of the Parallel Virtual Cluster (PVC) system
#
# Copyright (C) 2018-2020 Joshua M. Boniface <joshua@boniface.me>
#
# This program 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.
#
# 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 <https://www.gnu.org/licenses/>.
#
###############################################################################
import uuid
import time
import libvirt
import json
from threading import Thread
import pvcnoded.log as log
import pvcnoded.zkhandler as zkhandler
import pvcnoded.common as common
import pvcnoded.VMConsoleWatcherInstance as VMConsoleWatcherInstance
import daemon_lib.common as daemon_common
def flush_locks(zk_conn, logger, dom_uuid):
logger.out('Flushing RBD locks for VM "{}"'.format(dom_uuid), state='i')
# Get the list of RBD images
rbd_list = zkhandler.readdata(zk_conn, '/domains/{}/rbdlist'.format(dom_uuid)).split(',')
for rbd in rbd_list:
# Check if a lock exists
lock_list_retcode, lock_list_stdout, lock_list_stderr = common.run_os_command('rbd lock list --format json {}'.format(rbd))
if lock_list_retcode != 0:
logger.out('Failed to obtain lock list for volume "{}"'.format(rbd), state='e')
continue
try:
lock_list = json.loads(lock_list_stdout)
except Exception as e:
logger.out('Failed to parse lock list for volume "{}": {}'.format(rbd, e), state='e')
continue
# If there's at least one lock
if lock_list:
# Loop through the locks
for lock in lock_list:
# Free the lock
lock_remove_retcode, lock_remove_stdout, lock_remove_stderr = common.run_os_command('rbd lock remove {} "{}" "{}"'.format(rbd, lock['id'], lock['locker']))
if lock_remove_retcode != 0:
logger.out('Failed to free RBD lock "{}" on volume "{}"\n{}'.format(lock['id'], rbd, lock_remove_stderr), state='e')
continue
logger.out('Freed RBD lock "{}" on volume "{}"'.format(lock['id'], rbd), state='o')
return True
# Primary command function
def run_command(zk_conn, logger, this_node, data):
# Get the command and args
command, args = data.split()
# Flushing VM RBD locks
if command == 'flush_locks':
dom_uuid = args
# If this node is taking over primary state, wait until it's done
while this_node.router_state == 'takeover':
time.sleep(1)
if this_node.router_state == 'primary':
# Lock the command queue
zk_lock = zkhandler.writelock(zk_conn, '/cmd/domains')
with zk_lock:
# Add the OSD
result = flush_locks(zk_conn, logger, dom_uuid)
# Command succeeded
if result:
# Update the command queue
zkhandler.writedata(zk_conn, {'/cmd/domains': 'success-{}'.format(data)})
# Command failed
else:
# Update the command queue
zkhandler.writedata(zk_conn, {'/cmd/domains': 'failure-{}'.format(data)})
# Wait 1 seconds before we free the lock, to ensure the client hits the lock
time.sleep(1)
class VMInstance(object):
# Initialization function
def __init__(self, domuuid, zk_conn, config, logger, this_node):
# Passed-in variables on creation
self.domuuid = domuuid
self.zk_conn = zk_conn
self.config = config
self.logger = logger
self.this_node = this_node
# Get data from zookeeper
self.domname = zkhandler.readdata(zk_conn, '/domains/{}'.format(domuuid))
self.state = zkhandler.readdata(self.zk_conn, '/domains/{}/state'.format(self.domuuid))
self.node = zkhandler.readdata(self.zk_conn, '/domains/{}/node'.format(self.domuuid))
self.lastnode = zkhandler.readdata(self.zk_conn, '/domains/{}/lastnode'.format(self.domuuid))
self.last_currentnode = zkhandler.readdata(self.zk_conn, '/domains/{}/node'.format(self.domuuid))
self.last_lastnode = zkhandler.readdata(self.zk_conn, '/domains/{}/lastnode'.format(self.domuuid))
try:
self.pinpolicy = zkhandler.readdata(self.zk_conn, '/domains/{}/pinpolicy'.format(self.domuuid))
except:
self.pinpolicy = "None"
# These will all be set later
self.instart = False
self.inrestart = False
self.inmigrate = False
self.inreceive = False
self.inshutdown = False
self.instop = False
# Libvirt domuuid
self.dom = self.lookupByUUID(self.domuuid)
# Log watcher instance
self.console_log_instance = VMConsoleWatcherInstance.VMConsoleWatcherInstance(self.domuuid, self.domname, self.zk_conn, self.config, self.logger, self.this_node)
# Watch for changes to the state field in Zookeeper
@self.zk_conn.DataWatch('/domains/{}/state'.format(self.domuuid))
def watch_state(data, stat, event=""):
if event and event.type == 'DELETED':
# The key has been deleted after existing before; terminate this watcher
# because this class instance is about to be reaped in Daemon.py
return False
# Perform a management command
self.logger.out('Updating state of VM {}'.format(self.domuuid), state='i')
state_thread = Thread(target=self.manage_vm_state, args=(), kwargs={})
state_thread.start()
# Get data functions
def getstate(self):
return self.state
def getnode(self):
return self.node
def getlastnode(self):
return self.lastnode
def getdom(self):
return self.dom
def getmemory(self):
try:
if self.dom is not None:
memory = int(self.dom.info()[2] / 1024)
else:
domain_information = daemon_common.getInformationFromXML(self.zk_conn, self.domuuid)
memory = int(domain_information['memory'])
except:
memory = 0
return memory
def getvcpus(self):
try:
vcpus = int(self.dom.info()[3])
except:
vcpus = 0
return vcpus
# Manage local node domain_list
def addDomainToList(self):
if not self.domuuid in self.this_node.domain_list:
try:
# Add the domain to the domain_list array
self.this_node.domain_list.append(self.domuuid)
# Push the change up to Zookeeper
zkhandler.writedata(self.zk_conn, { '/nodes/{}/runningdomains'.format(self.this_node.name): ' '.join(self.this_node.domain_list) })
except Exception as e:
self.logger.out('Error adding domain to list: {}'.format(e), state='e')
def removeDomainFromList(self):
if self.domuuid in self.this_node.domain_list:
try:
# Remove the domain from the domain_list array
self.this_node.domain_list.remove(self.domuuid)
# Push the change up to Zookeeper
zkhandler.writedata(self.zk_conn, { '/nodes/{}/runningdomains'.format(self.this_node.name): ' '.join(self.this_node.domain_list) })
except Exception as e:
self.logger.out('Error removing domain from list: {}'.format(e), state='e')
# Start up the VM
def start_vm(self):
# Start the log watcher
self.console_log_instance.start()
self.logger.out('Starting VM', state='i', prefix='Domain {}'.format(self.domuuid))
self.instart = True
# Start up a new Libvirt connection
libvirt_name = "qemu:///system"
lv_conn = libvirt.open(libvirt_name)
if lv_conn == None:
self.logger.out('Failed to open local libvirt connection', state='e', prefix='Domain {}'.format(self.domuuid))
self.instart = False
return
# Try to get the current state in case it's already running
try:
self.dom = self.lookupByUUID(self.domuuid)
curstate = self.dom.state()[0]
except:
curstate = 'notstart'
if curstate == libvirt.VIR_DOMAIN_RUNNING:
# If it is running just update the model
self.addDomainToList()
zkhandler.writedata(self.zk_conn, { '/domains/{}/failedreason'.format(self.domuuid): '' })
else:
# Or try to create it
try:
# Grab the domain information from Zookeeper
xmlconfig = zkhandler.readdata(self.zk_conn, '/domains/{}/xml'.format(self.domuuid))
dom = lv_conn.createXML(xmlconfig, 0)
self.addDomainToList()
self.logger.out('Successfully started VM', state='o', prefix='Domain {}'.format(self.domuuid))
self.dom = dom
zkhandler.writedata(self.zk_conn, { '/domains/{}/failedreason'.format(self.domuuid): '' })
except libvirt.libvirtError as e:
self.logger.out('Failed to create VM', state='e', prefix='Domain {}'.format(self.domuuid))
zkhandler.writedata(self.zk_conn, { '/domains/{}/state'.format(self.domuuid): 'fail' })
zkhandler.writedata(self.zk_conn, { '/domains/{}/failedreason'.format(self.domuuid): str(e) })
self.dom = None
lv_conn.close()
self.instart = False
# Restart the VM
def restart_vm(self):
self.logger.out('Restarting VM', state='i', prefix='Domain {}'.format(self.domuuid))
self.inrestart = True
# Start up a new Libvirt connection
libvirt_name = "qemu:///system"
lv_conn = libvirt.open(libvirt_name)
if lv_conn == None:
self.logger.out('Failed to open local libvirt connection', state='e', prefix='Domain {}'.format(self.domuuid))
self.inrestart = False
return
self.shutdown_vm()
time.sleep(0.2)
self.start_vm()
self.addDomainToList()
zkhandler.writedata(self.zk_conn, { '/domains/{}/state'.format(self.domuuid): 'start' })
lv_conn.close()
self.inrestart = False
# Stop the VM forcibly without updating state
def terminate_vm(self):
self.logger.out('Terminating VM', state='i', prefix='Domain {}'.format(self.domuuid))
self.instop = True
try:
self.dom.destroy()
except AttributeError:
self.logger.out('Failed to terminate VM', state='e', prefix='Domain {}'.format(self.domuuid))
self.removeDomainFromList()
self.logger.out('Successfully terminated VM', state='o', prefix='Domain {}'.format(self.domuuid))
self.dom = None
self.instop = False
# Stop the log watcher
self.console_log_instance.stop()
# Stop the VM forcibly
def stop_vm(self):
self.logger.out('Forcibly stopping VM', state='i', prefix='Domain {}'.format(self.domuuid))
self.instop = True
try:
self.dom.destroy()
except AttributeError:
self.logger.out('Failed to stop VM', state='e', prefix='Domain {}'.format(self.domuuid))
self.removeDomainFromList()
if self.inrestart == False:
zkhandler.writedata(self.zk_conn, { '/domains/{}/state'.format(self.domuuid): 'stop' })
self.logger.out('Successfully stopped VM', state='o', prefix='Domain {}'.format(self.domuuid))
self.dom = None
self.instop = False
# Stop the log watcher
self.console_log_instance.stop()
# Shutdown the VM gracefully
def shutdown_vm(self):
self.logger.out('Gracefully stopping VM', state='i', prefix='Domain {}'.format(self.domuuid))
is_aborted = False
self.inshutdown = True
self.dom.shutdown()
tick = 0
while True:
tick += 1
time.sleep(1)
# Abort shutdown if the state changes to start
current_state = zkhandler.readdata(self.zk_conn, '/domains/{}/state'.format(self.domuuid))
if current_state not in ['shutdown', 'restart']:
self.logger.out('Aborting VM shutdown due to state change', state='i', prefix='Domain {}'.format(self.domuuid))
is_aborted = True
break
try:
lvdomstate = self.dom.state()[0]
except:
lvdomstate = None
if lvdomstate != libvirt.VIR_DOMAIN_RUNNING:
self.removeDomainFromList()
zkhandler.writedata(self.zk_conn, { '/domains/{}/state'.format(self.domuuid): 'stop' })
self.logger.out('Successfully shutdown VM', state='o', prefix='Domain {}'.format(self.domuuid))
self.dom = None
# Stop the log watcher
self.console_log_instance.stop()
break
if tick >= self.config['vm_shutdown_timeout']:
self.logger.out('Shutdown timeout ({}s) expired, forcing off'.format(self.config['vm_shutdown_timeout']), state='e', prefix='Domain {}'.format(self.domuuid))
zkhandler.writedata(self.zk_conn, { '/domains/{}/state'.format(self.domuuid): 'stop' })
break
self.inshutdown = False
if is_aborted:
self.manage_vm_state()
if self.inrestart:
# Wait to prevent race conditions
time.sleep(1)
zkhandler.writedata(self.zk_conn, { '/domains/{}/state'.format(self.domuuid): 'start' })
# Migrate the VM to a target host
def migrate_vm(self, force_live=False):
# Wait for any previous migration
while self.inmigrate:
time.sleep(0.1)
self.inmigrate = True
self.logger.out('Migrating VM to node "{}"'.format(self.node), state='i', prefix='Domain {}'.format(self.domuuid))
# Used for sanity checking later
target_node = zkhandler.readdata(self.zk_conn, '/domains/{}/node'.format(self.domuuid))
aborted = False
def abort_migrate(reason):
zkhandler.writedata(self.zk_conn, {
'/domains/{}/state'.format(self.domuuid): 'start',
'/domains/{}/node'.format(self.domuuid): self.this_node.name,
'/domains/{}/lastnode'.format(self.domuuid): self.last_lastnode
})
migrate_lock_node.release()
migrate_lock_state.release()
self.logger.out('Aborted migration: {}'.format(reason), state='i', prefix='Domain {}'.format(self.domuuid))
# Acquire exclusive lock on the domain node key
migrate_lock_node = zkhandler.exclusivelock(self.zk_conn, '/domains/{}/node'.format(self.domuuid))
migrate_lock_state = zkhandler.exclusivelock(self.zk_conn, '/domains/{}/state'.format(self.domuuid))
migrate_lock_node.acquire()
migrate_lock_state.acquire()
time.sleep(0.2) # Initial delay for the first writer to grab the lock
# Don't try to migrate a node to itself, set back to start
if self.node == self.lastnode or self.node == self.this_node.name:
abort_migrate('Target node matches the current active node during initial check')
return
# Synchronize nodes A (I am reader)
lock = zkhandler.readlock(self.zk_conn, '/locks/domain_migrate/{}'.format(self.domuuid))
self.logger.out('Acquiring read lock for synchronization phase A', state='i', prefix='Domain {}'.format(self.domuuid))
lock.acquire()
self.logger.out('Acquired read lock for synchronization phase A', state='o', prefix='Domain {}'.format(self.domuuid))
if zkhandler.readdata(self.zk_conn, '/locks/domain_migrate/{}'.format(self.domuuid)) == '':
self.logger.out('Waiting for peer', state='i', prefix='Domain {}'.format(self.domuuid))
ticks = 0
while zkhandler.readdata(self.zk_conn, '/locks/domain_migrate/{}'.format(self.domuuid)) == '':
time.sleep(0.1)
ticks += 1
if ticks > 300:
self.logger.out('Timed out waiting 30s for peer', state='e', prefix='Domain {}'.format(self.domuuid))
aborted = True
break
self.logger.out('Releasing read lock for synchronization phase A', state='i', prefix='Domain {}'.format(self.domuuid))
lock.release()
self.logger.out('Released read lock for synchronization phase A', state='o', prefix='Domain {}'.format(self.domuuid))
if aborted:
abort_migrate('Timed out waiting for peer')
return
# Synchronize nodes B (I am writer)
lock = zkhandler.writelock(self.zk_conn, '/locks/domain_migrate/{}'.format(self.domuuid))
self.logger.out('Acquiring write lock for synchronization phase B', state='i', prefix='Domain {}'.format(self.domuuid))
lock.acquire()
self.logger.out('Acquired write lock for synchronization phase B', state='o', prefix='Domain {}'.format(self.domuuid))
time.sleep(0.5) # Time for reader to acquire the lock
def migrate_live():
self.logger.out('Setting up live migration', state='i', prefix='Domain {}'.format(self.domuuid))
# Set up destination connection
dest_lv = 'qemu+tcp://{}.{}/system'.format(self.node, self.config['cluster_domain'])
dest_tcp = 'tcp://{}.{}'.format(self.node, self.config['cluster_domain'])
try:
self.logger.out('Opening remote libvirt connection', state='i', prefix='Domain {}'.format(self.domuuid))
# Open a connection to the destination
dest_lv_conn = libvirt.open(dest_lv)
if not dest_lv_conn:
raise
except:
self.logger.out('Failed to open connection to {}; aborting live migration.'.format(dest_lv), state='e', prefix='Domain {}'.format(self.domuuid))
return False
try:
self.logger.out('Live migrating VM', state='i', prefix='Domain {}'.format(self.domuuid))
# Send the live migration; force the destination URI to ensure we transit over the cluster network
target_dom = self.dom.migrate(dest_lv_conn, libvirt.VIR_MIGRATE_LIVE, None, dest_tcp, 0)
if not target_dom:
raise
except Exception as e:
self.logger.out('Failed to send VM to {} - aborting live migration; error: {}'.format(dest_lv, e), state='e', prefix='Domain {}'.format(self.domuuid))
dest_lv_conn.close()
return False
self.logger.out('Successfully migrated VM', state='o', prefix='Domain {}'.format(self.domuuid))
dest_lv_conn.close()
self.console_log_instance.stop()
self.removeDomainFromList()
return True
def migrate_shutdown():
self.logger.out('Shutting down VM for offline migration', state='i', prefix='Domain {}'.format(self.domuuid))
zkhandler.writedata(self.zk_conn, { '/domains/{}/state'.format(self.domuuid): 'shutdown' })
while zkhandler.readdata(self.zk_conn, '/domains/{}/state'.format(self.domuuid)) != 'stop':
time.sleep(0.5)
return True
do_migrate_shutdown = False
migrate_live_result = False
# Do a final verification
if self.node == self.lastnode or self.node == self.this_node.name:
abort_migrate('Target node matches the current active node during final check')
return
if self.node != target_node:
abort_migrate('Target node changed during preparation')
return
# A live migrate is attemped 3 times in succession
ticks = 0
while True:
ticks += 1
self.logger.out('Attempting live migration try {}'.format(ticks), state='i', prefix='Domain {}'.format(self.domuuid))
migrate_live_result = migrate_live()
if migrate_live_result:
break
time.sleep(0.5)
if ticks > 2:
break
if not migrate_live_result:
if force_live:
self.logger.out('Could not live migrate VM while live migration enforced', state='e', prefix='Domain {}'.format(self.domuuid))
aborted = True
else:
do_migrate_shutdown = True
self.logger.out('Releasing write lock for synchronization phase B', state='i', prefix='Domain {}'.format(self.domuuid))
lock.release()
self.logger.out('Released write lock for synchronization phase B', state='o', prefix='Domain {}'.format(self.domuuid))
if aborted:
abort_migrate('Live migration failed and is required')
return
# Synchronize nodes C (I am writer)
lock = zkhandler.writelock(self.zk_conn, '/locks/domain_migrate/{}'.format(self.domuuid))
self.logger.out('Acquiring write lock for synchronization phase C', state='i', prefix='Domain {}'.format(self.domuuid))
lock.acquire()
self.logger.out('Acquired write lock for synchronization phase C', state='o', prefix='Domain {}'.format(self.domuuid))
time.sleep(0.5) # Time for reader to acquire the lock
if do_migrate_shutdown:
migrate_shutdown_result = migrate_shutdown()
self.logger.out('Releasing write lock for synchronization phase C', state='i', prefix='Domain {}'.format(self.domuuid))
lock.release()
self.logger.out('Released write lock for synchronization phase C', state='o', prefix='Domain {}'.format(self.domuuid))
# Synchronize nodes D (I am reader)
lock = zkhandler.readlock(self.zk_conn, '/locks/domain_migrate/{}'.format(self.domuuid))
self.logger.out('Acquiring read lock for synchronization phase D', state='i', prefix='Domain {}'.format(self.domuuid))
lock.acquire()
self.logger.out('Acquired read lock for synchronization phase D', state='o', prefix='Domain {}'.format(self.domuuid))
self.last_currentnode = zkhandler.readdata(self.zk_conn, '/domains/{}/node'.format(self.domuuid))
self.last_lastnode = zkhandler.readdata(self.zk_conn, '/domains/{}/lastnode'.format(self.domuuid))
self.logger.out('Releasing read lock for synchronization phase D', state='i', prefix='Domain {}'.format(self.domuuid))
lock.release()
self.logger.out('Released read lock for synchronization phase D', state='o', prefix='Domain {}'.format(self.domuuid))
# Wait 0.5 seconds for everything to stabilize before we declare all-done
time.sleep(0.5)
migrate_lock_node.release()
migrate_lock_state.release()
self.inmigrate = False
return
# Receive the migration from another host
def receive_migrate(self):
# Wait for any previous migration
while self.inreceive:
time.sleep(0.1)
self.inreceive = True
live_receive = True
self.logger.out('Receiving VM migration from node "{}"'.format(self.node), state='i', prefix='Domain {}'.format(self.domuuid))
# Ensure our lock key is populated
zkhandler.writedata(self.zk_conn, { '/locks/domain_migrate/{}'.format(self.domuuid): self.domuuid })
# Synchronize nodes A (I am writer)
lock = zkhandler.writelock(self.zk_conn, '/locks/domain_migrate/{}'.format(self.domuuid))
self.logger.out('Acquiring write lock for synchronization phase A', state='i', prefix='Domain {}'.format(self.domuuid))
lock.acquire()
self.logger.out('Acquired write lock for synchronization phase A', state='o', prefix='Domain {}'.format(self.domuuid))
time.sleep(0.5) # Time for reader to acquire the lock
self.logger.out('Releasing write lock for synchronization phase A', state='i', prefix='Domain {}'.format(self.domuuid))
lock.release()
self.logger.out('Released write lock for synchronization phase A', state='o', prefix='Domain {}'.format(self.domuuid))
time.sleep(0.1) # Time for new writer to acquire the lock
# Synchronize nodes B (I am reader)
lock = zkhandler.readlock(self.zk_conn, '/locks/domain_migrate/{}'.format(self.domuuid))
self.logger.out('Acquiring read lock for synchronization phase B', state='i', prefix='Domain {}'.format(self.domuuid))
lock.acquire()
self.logger.out('Acquired read lock for synchronization phase B', state='o', prefix='Domain {}'.format(self.domuuid))
self.logger.out('Releasing read lock for synchronization phase B', state='i', prefix='Domain {}'.format(self.domuuid))
lock.release()
self.logger.out('Released read lock for synchronization phase B', state='o', prefix='Domain {}'.format(self.domuuid))
# Synchronize nodes C (I am reader)
lock = zkhandler.readlock(self.zk_conn, '/locks/domain_migrate/{}'.format(self.domuuid))
self.logger.out('Acquiring read lock for synchronization phase C', state='i', prefix='Domain {}'.format(self.domuuid))
lock.acquire()
self.logger.out('Acquired read lock for synchronization phase C', state='o', prefix='Domain {}'.format(self.domuuid))
# Set the updated data
self.last_currentnode = zkhandler.readdata(self.zk_conn, '/domains/{}/node'.format(self.domuuid))
self.last_lastnode = zkhandler.readdata(self.zk_conn, '/domains/{}/lastnode'.format(self.domuuid))
self.logger.out('Releasing read lock for synchronization phase C', state='i', prefix='Domain {}'.format(self.domuuid))
lock.release()
self.logger.out('Released read lock for synchronization phase C', state='o', prefix='Domain {}'.format(self.domuuid))
# Synchronize nodes D (I am writer)
lock = zkhandler.writelock(self.zk_conn, '/locks/domain_migrate/{}'.format(self.domuuid))
self.logger.out('Acquiring write lock for synchronization phase D', state='i', prefix='Domain {}'.format(self.domuuid))
lock.acquire()
self.logger.out('Acquired write lock for synchronization phase D', state='o', prefix='Domain {}'.format(self.domuuid))
time.sleep(0.5) # Time for reader to acquire the lock
self.state = zkhandler.readdata(self.zk_conn, '/domains/{}/state'.format(self.domuuid))
self.dom = self.lookupByUUID(self.domuuid)
if self.dom:
lvdomstate = self.dom.state()[0]
if lvdomstate == libvirt.VIR_DOMAIN_RUNNING:
# VM has been received and started
self.addDomainToList()
zkhandler.writedata(self.zk_conn, { '/domains/{}/state'.format(self.domuuid): 'start' })
self.logger.out('Successfully received migrated VM', state='o', prefix='Domain {}'.format(self.domuuid))
else:
# The receive somehow failed
zkhandler.writedata(self.zk_conn, { '/domains/{}/state'.format(self.domuuid): 'fail' })
else:
if self.state in ['start']:
# The receive was aborted
self.logger.out('Receive aborted via state change', state='w', prefix='Domain {}'.format(self.domuuid))
elif self.state in ['stop']:
# The send was shutdown-based
zkhandler.writedata(self.zk_conn, { '/domains/{}/state'.format(self.domuuid): 'start' })
else:
# The send failed or was aborted
self.logger.out('Migrate aborted or failed; VM in state {}'.format(self.state), state='w', prefix='Domain {}'.format(self.domuuid))
self.logger.out('Releasing write lock for synchronization phase D', state='i', prefix='Domain {}'.format(self.domuuid))
zkhandler.writedata(self.zk_conn, { '/locks/domain_migrate/{}'.format(self.domuuid): '' })
lock.release()
self.logger.out('Released write lock for synchronization phase D', state='o', prefix='Domain {}'.format(self.domuuid))
time.sleep(0.1) # Time for new writer to acquire the lock
self.inreceive = False
return
#
# Main function to manage a VM (taking only self)
#
def manage_vm_state(self):
# Update the current values from zookeeper
self.state = zkhandler.readdata(self.zk_conn, '/domains/{}/state'.format(self.domuuid))
self.node = zkhandler.readdata(self.zk_conn, '/domains/{}/node'.format(self.domuuid))
self.lastnode = zkhandler.readdata(self.zk_conn, '/domains/{}/lastnode'.format(self.domuuid))
# Check the current state of the VM
try:
if self.dom != None:
running, reason = self.dom.state()
else:
raise
except:
running = libvirt.VIR_DOMAIN_NOSTATE
self.logger.out('VM state change for "{}": {} {}'.format(self.domuuid, self.state, self.node), state='i')
#######################
# Handle state changes
#######################
# Valid states are:
# start
# migrate
# migrate-live
# restart
# shutdown
# stop
# States we don't (need to) handle are:
# disable
# provision
# Conditional pass one - Are we already performing an action
if self.instart == False \
and self.inrestart == False \
and self.inmigrate == False \
and self.inreceive == False \
and self.inshutdown == False \
and self.instop == False:
# Conditional pass two - Is this VM configured to run on this node
if self.node == self.this_node.name:
# Conditional pass three - Is this VM currently running on this node
if running == libvirt.VIR_DOMAIN_RUNNING:
# VM is already running and should be
if self.state == "start":
# Start the log watcher
self.console_log_instance.start()
# Add domain to running list
self.addDomainToList()
# VM is already running and should be but stuck in migrate state
elif self.state == "migrate" or self.state == "migrate-live":
# Start the log watcher
self.console_log_instance.start()
zkhandler.writedata(self.zk_conn, { '/domains/{}/state'.format(self.domuuid): 'start' })
# Add domain to running list
self.addDomainToList()
# VM should be restarted
elif self.state == "restart":
self.restart_vm()
# VM should be shut down
elif self.state == "shutdown":
self.shutdown_vm()
# VM should be stopped
elif self.state == "stop":
self.stop_vm()
else:
# VM should be started
if self.state == "start":
# Start the domain
self.start_vm()
# VM should be migrated to this node
elif self.state == "migrate" or self.state == "migrate-live":
# Receive the migration
self.receive_migrate()
# VM should be restarted (i.e. started since it isn't running)
if self.state == "restart":
zkhandler.writedata(self.zk_conn, { '/domains/{}/state'.format(self.domuuid): 'start' })
# VM should be shut down; ensure it's gone from this node's domain_list
elif self.state == "shutdown":
self.removeDomainFromList()
# Stop the log watcher
self.console_log_instance.stop()
# VM should be stoped; ensure it's gone from this node's domain_list
elif self.state == "stop":
self.removeDomainFromList()
# Stop the log watcher
self.console_log_instance.stop()
else:
# Conditional pass three - Is this VM currently running on this node
if running == libvirt.VIR_DOMAIN_RUNNING:
# VM should be migrated away from this node
if self.state == "migrate":
self.migrate_vm(force_live=False)
# VM should be migrated away from this node, live only (no shutdown fallback)
elif self.state == "migrate-live":
self.migrate_vm(force_live=True)
# VM should be shutdown gracefully
elif self.state == 'shutdown':
self.shutdown_vm()
# VM should be forcibly terminated
else:
self.terminate_vm()
# This function is a wrapper for libvirt.lookupByUUID which fixes some problems
# 1. Takes a text UUID and handles converting it to bytes
# 2. Try's it and returns a sensible value if not
def lookupByUUID(self, tuuid):
# Don't do anything if the VM shouldn't live on this node
if self.node != self.this_node.name:
return None
lv_conn = None
libvirt_name = "qemu:///system"
# Convert the text UUID to bytes
buuid = uuid.UUID(tuuid).bytes
# Try
try:
# Open a libvirt connection
lv_conn = libvirt.open(libvirt_name)
if lv_conn == None:
self.logger.out('Failed to open local libvirt connection', state='e', prefix='Domain {}'.format(self.domuuid))
return None
# Lookup the UUID
dom = lv_conn.lookupByUUID(buuid)
# Fail
except:
dom = None
# After everything
finally:
# Close the libvirt connection
if lv_conn != None:
lv_conn.close()
# Return the dom object (or None)
return dom