334 lines
13 KiB
Python
334 lines
13 KiB
Python
#!/usr/bin/env python3
|
|
|
|
# VMInstance.py - Class implementing a PVC virtual machine and run by pvcd
|
|
# Part of the Parallel Virtual Cluster (PVC) system
|
|
#
|
|
# Copyright (C) 2018 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 os, sys, uuid, socket, time, threading, libvirt, kazoo.client, ansiiprint
|
|
|
|
class VMInstance:
|
|
# Initialization function
|
|
def __init__(self, domuuid, zk, config, thishypervisor):
|
|
# Passed-in variables on creation
|
|
self.domuuid = domuuid
|
|
self.zk = zk
|
|
self.config = config
|
|
self.thishypervisor = thishypervisor
|
|
|
|
# These will all be set later
|
|
self.hypervisor = None
|
|
self.state = None
|
|
self.instart = False
|
|
self.instop = False
|
|
self.inshutdown = False
|
|
self.inmigrate = False
|
|
self.inreceive = False
|
|
|
|
# These stop a weird clobber at startup
|
|
self.noclobber = False
|
|
|
|
self.dom = self.lookupByUUID(self.domuuid)
|
|
|
|
# Watch for changes to the state field in Zookeeper
|
|
@zk.DataWatch('/domains/{}/state'.format(self.domuuid))
|
|
def watch_state(data, stat, event=""):
|
|
if self.noclobber == False:
|
|
self.noclobber = True
|
|
self.manage_vm_state()
|
|
|
|
# Watch for changes to the hypervisor field in Zookeeper
|
|
@zk.DataWatch('/domains/{}/hypervisor'.format(self.domuuid))
|
|
def watch_hypervisor(data, stat, event=""):
|
|
if self.noclobber == False:
|
|
self.noclobber = True
|
|
self.manage_vm_state()
|
|
|
|
# Get data functions
|
|
def getstate(self):
|
|
return self.state
|
|
|
|
def gethypervisor(self):
|
|
return self.hypervisor
|
|
|
|
# Allow the node to set the noclobber status once it performs its first keepalive
|
|
def setnoclobber(self):
|
|
self.noclobber = False
|
|
|
|
# Start up the VM
|
|
def start_vm(self, xmlconfig):
|
|
ansiiprint.echo('Starting VM', '{}:'.format(self.domuuid), 'i')
|
|
self.instart = True
|
|
|
|
# Start up a new Libvirt connection
|
|
libvirt_name = "qemu:///system"
|
|
conn = libvirt.open(libvirt_name)
|
|
if conn == None:
|
|
ansiiprint.echo('Failed to open local libvirt connection', '{}:'.format(self.domuuid), 'e')
|
|
self.instart = False
|
|
return
|
|
|
|
try:
|
|
dom = conn.createXML(xmlconfig, 0)
|
|
if not self.domuuid in self.thishypervisor.domain_list:
|
|
self.thishypervisor.domain_list.append(self.domuuid)
|
|
|
|
ansiiprint.echo('Successfully started VM', '{}:'.format(self.domuuid), 'o')
|
|
self.dom = dom
|
|
except libvirt.libvirtError as e:
|
|
ansiiprint.echo('Failed to create VM', '{}:'.format(self.domuuid), 'e')
|
|
self.zk.set('/domains/{}/state'.format(self.domuuid), 'stop'.encode('ascii'))
|
|
self.dom = None
|
|
|
|
conn.close()
|
|
self.instart = False
|
|
|
|
# Stop the VM forcibly without updating state
|
|
def terminate_vm(self):
|
|
ansiiprint.echo('Terminating VM', '{}:'.format(self.domuuid), 'i')
|
|
self.instop = True
|
|
try:
|
|
self.dom.destroy()
|
|
except AttributeError:
|
|
ansiiprint.echo('Failed to terminate VM', '{}:'.format(self.domuuid), 'e')
|
|
if self.domuuid in self.thishypervisor.domain_list:
|
|
try:
|
|
self.thishypervisor.domain_list.remove(self.domuuid)
|
|
except ValueError:
|
|
pass
|
|
ansiiprint.echo('Successfully terminated VM', '{}:'.format(self.domuuid), 'o')
|
|
self.instop = False
|
|
|
|
# Stop the VM forcibly
|
|
def stop_vm(self):
|
|
ansiiprint.echo('Forcibly stopping VM', '{}:'.format(self.domuuid), 'i')
|
|
self.instop = True
|
|
try:
|
|
self.dom.destroy()
|
|
except AttributeError:
|
|
ansiiprint.echo('Failed to stop VM', '{}:'.format(self.domuuid), 'e')
|
|
if self.domuuid in self.thishypervisor.domain_list:
|
|
try:
|
|
self.thishypervisor.domain_list.remove(self.domuuid)
|
|
except ValueError:
|
|
pass
|
|
|
|
self.zk.set('/domains/{}/state'.format(self.domuuid), 'stop'.encode('ascii'))
|
|
ansiiprint.echo('Successfully stopped VM', '{}:'.format(self.domuuid), 'o')
|
|
self.dom = None
|
|
self.instop = False
|
|
|
|
# Shutdown the VM gracefully
|
|
def shutdown_vm(self):
|
|
ansiiprint.echo('Gracefully stopping VM', '{}:'.format(self.domuuid), 'i')
|
|
self.inshutdown = True
|
|
self.dom.shutdown()
|
|
try:
|
|
tick = 0
|
|
while self.dom.state()[0] == libvirt.VIR_DOMAIN_RUNNING and tick < 60:
|
|
tick += 1
|
|
time.sleep(0.5)
|
|
|
|
if tick >= 60:
|
|
ansiiprint.echo('Shutdown timeout expired', '{}:'.format(self.domuuid), 'e')
|
|
self.stop_vm()
|
|
self.inshutdown = False
|
|
return
|
|
except:
|
|
pass
|
|
|
|
if self.domuuid in self.thishypervisor.domain_list:
|
|
try:
|
|
self.thishypervisor.domain_list.remove(self.domuuid)
|
|
except ValueError:
|
|
pass
|
|
|
|
self.zk.set('/domains/{}/state'.format(self.domuuid), 'stop'.encode('ascii'))
|
|
ansiiprint.echo('Successfully shutdown VM', '{}:'.format(self.domuuid), 'o')
|
|
self.dom = None
|
|
self.inshutdown = False
|
|
|
|
def live_migrate_vm(self, dest_hypervisor):
|
|
try:
|
|
dest_conn = libvirt.open('qemu+tcp://{}/system'.format(self.hypervisor))
|
|
if dest_conn == None:
|
|
raise
|
|
except:
|
|
ansiiprint.echo('Failed to open connection to qemu+tcp://{}/system; aborting migration.'.format(self.hypervisor), '{}:'.format(self.domuuid), 'e')
|
|
return 1
|
|
|
|
try:
|
|
target_dom = self.dom.migrate(dest_conn, libvirt.VIR_MIGRATE_LIVE, None, None, 0)
|
|
if target_dom == None:
|
|
raise
|
|
ansiiprint.echo('Successfully migrated VM', '{}:'.format(self.domuuid), 'o')
|
|
|
|
except:
|
|
dest_conn.close()
|
|
return 1
|
|
|
|
dest_conn.close()
|
|
return 0
|
|
|
|
# Migrate the VM to a target host
|
|
def migrate_vm(self):
|
|
self.inmigrate = True
|
|
ansiiprint.echo('Migrating VM to hypervisor "{}"'.format(self.hypervisor), '{}:'.format(self.domuuid), 'i')
|
|
migrate_ret = self.live_migrate_vm(self.hypervisor)
|
|
if migrate_ret != 0:
|
|
ansiiprint.echo('Could not live migrate VM; shutting down to migrate instead', '{}:'.format(self.domuuid), 'e')
|
|
self.shutdown_vm()
|
|
time.sleep(1)
|
|
self.zk.set('/domains/{}/state'.format(self.domuuid), 'start'.encode('ascii'))
|
|
else:
|
|
try:
|
|
self.thishypervisor.domain_list.remove(self.domuuid)
|
|
except ValueError:
|
|
pass
|
|
time.sleep(1)
|
|
self.zk.set('/domains/{}/state'.format(self.domuuid), 'start'.encode('ascii'))
|
|
|
|
self.inmigrate = False
|
|
|
|
# Receive the migration from another host (wait until VM is running)
|
|
def receive_migrate(self):
|
|
self.inreceive = True
|
|
ansiiprint.echo('Receiving migration', '{}:'.format(self.domuuid), 'i')
|
|
while True:
|
|
self.state = self.zk.get('/domains/{}/state'.format(self.domuuid))[0].decode('ascii')
|
|
self.dom = self.lookupByUUID(self.domuuid)
|
|
|
|
if self.dom == None and self.state == 'migrate':
|
|
continue
|
|
|
|
if self.state != 'migrate':
|
|
break
|
|
|
|
try:
|
|
if self.dom.state()[0] == libvirt.VIR_DOMAIN_RUNNING:
|
|
break
|
|
except:
|
|
continue
|
|
|
|
if self.dom.state()[0] == libvirt.VIR_DOMAIN_RUNNING:
|
|
if not self.domuuid in self.thishypervisor.domain_list:
|
|
self.thishypervisor.domain_list.append(self.domuuid)
|
|
ansiiprint.echo('Successfully received migrated VM', '{}:'.format(self.domuuid), 'o')
|
|
self.zk.set('/domains/{}/state'.format(self.domuuid), 'start'.encode('ascii'))
|
|
else:
|
|
ansiiprint.echo('Failed to receive migrated VM', '{}:'.format(self.domuuid), 'e')
|
|
self.zk.set('/domains/{}/state'.format(self.domuuid), 'start'.encode('ascii'))
|
|
|
|
self.inreceive = False
|
|
|
|
#
|
|
# Main function to manage a VM (taking only self)
|
|
#
|
|
def manage_vm_state(self):
|
|
# Get the current values from zookeeper
|
|
self.state = self.zk.get('/domains/{}/state'.format(self.domuuid))[0].decode('ascii')
|
|
self.hypervisor = self.zk.get('/domains/{}/hypervisor'.format(self.domuuid))[0].decode('ascii')
|
|
|
|
# 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
|
|
|
|
ansiiprint.echo('VM state change for "{}": {} {}'.format(self.domuuid, self.state, self.hypervisor), '', 'i')
|
|
|
|
# Conditional pass one - If we're already doing something, bail out
|
|
if self.instart == True or self.instop == True or self.inshutdown == True or self.inmigrate == True or self.inreceive == True:
|
|
return 0
|
|
|
|
# VM should be stopped
|
|
if running == libvirt.VIR_DOMAIN_RUNNING and self.state == "stop" and self.hypervisor == self.thishypervisor.name:
|
|
self.stop_vm()
|
|
|
|
# VM should be shut down
|
|
elif running == libvirt.VIR_DOMAIN_RUNNING and self.state == "shutdown" and self.hypervisor == self.thishypervisor.name:
|
|
self.shutdown_vm()
|
|
|
|
# VM should be migrated to this hypervisor
|
|
elif running != libvirt.VIR_DOMAIN_RUNNING and self.state == "migrate" and self.hypervisor == self.thishypervisor.name:
|
|
self.receive_migrate()
|
|
|
|
# VM should be migrated away from this hypervisor
|
|
elif running == libvirt.VIR_DOMAIN_RUNNING and self.state == "migrate" and self.hypervisor != self.thishypervisor.name:
|
|
self.migrate_vm()
|
|
|
|
# VM should be running but not on this hypervisor
|
|
elif running == libvirt.VIR_DOMAIN_RUNNING and self.state == "start" and self.hypervisor != self.thishypervisor.name:
|
|
self.terminate_vm()
|
|
|
|
# VM is already running and should be
|
|
elif running == libvirt.VIR_DOMAIN_RUNNING and self.state == "start" and self.hypervisor == self.thishypervisor.name:
|
|
if not self.domuuid in self.thishypervisor.domain_list:
|
|
self.thishypervisor.domain_list.append(self.domuuid)
|
|
|
|
# VM is already running and should be but stuck in migrate state
|
|
elif running == libvirt.VIR_DOMAIN_RUNNING and self.state == "migrate" and self.hypervisor == self.thishypervisor.name:
|
|
self.zk.set('/domains/{}/state'.format(self.domuuid), 'start'.encode('ascii'))
|
|
if not self.domuuid in self.thishypervisor.domain_list:
|
|
self.thishypervisor.domain_list.append(self.domuuid)
|
|
|
|
# VM should be started
|
|
elif running != libvirt.VIR_DOMAIN_RUNNING and self.state == "start" and self.hypervisor == self.thishypervisor.name:
|
|
# Grab the domain information from Zookeeper
|
|
domxml, domxmlstat = self.zk.get('/domains/{}/xml'.format(self.domuuid))
|
|
domxml = str(domxml.decode('ascii'))
|
|
self.start_vm(domxml)
|
|
|
|
# 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):
|
|
conn = None
|
|
dom = None
|
|
libvirt_name = "qemu:///system"
|
|
|
|
# Convert the text UUID to bytes
|
|
buuid = uuid.UUID(tuuid).bytes
|
|
|
|
# Try
|
|
try:
|
|
# Open a libvirt connection
|
|
conn = libvirt.open(libvirt_name)
|
|
if conn == None:
|
|
ansiiprint.echo('Failed to open local libvirt connection', '{}:'.format(self.domuuid), 'e')
|
|
return dom
|
|
|
|
# Lookup the UUID
|
|
dom = conn.lookupByUUID(buuid)
|
|
|
|
# Fail
|
|
except:
|
|
pass
|
|
|
|
# After everything
|
|
finally:
|
|
# Close the libvirt connection
|
|
if conn != None:
|
|
conn.close()
|
|
|
|
# Return the dom object (or None)
|
|
return dom
|