pvc/pvcd/NodeInstance.py

502 lines
21 KiB
Python

#!/usr/bin/env python3
# NodeInstance.py - Class implementing a PVC node 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, psutil, socket, time, libvirt, kazoo.client, threading, subprocess
import pvcd.ansiiprint as ansiiprint
import pvcd.zkhandler as zkhandler
class NodeInstance():
# Initialization function
def __init__(self, this_node, name, t_node, s_domain, zk_conn, config):
# Passed-in variables on creation
self.zk_conn = zk_conn
self.config = config
self.this_node = this_node
self.name = name
self.daemon_state = 'stop'
self.domain_state = 'ready'
self.t_node = t_node
self.active_node_list = []
self.flushed_node_list = []
self.inactive_node_list = []
self.s_domain = s_domain
self.domain_list = []
self.ipmi_hostname = self.config['ipmi_hostname']
self.domains_count = 0
self.memused = 0
self.memfree = 0
self.memalloc = 0
self.vcpualloc = 0
self.inflush = False
# Zookeeper handlers for changed states
@zk_conn.DataWatch('/nodes/{}/daemonstate'.format(self.name))
def watch_hypervisor_daemonstate(data, stat, event=""):
try:
self.daemon_state = data.decode('ascii')
except AttributeError:
self.daemon_state = 'stop'
@zk_conn.DataWatch('/nodes/{}/domainstate'.format(self.name))
def watch_hypervisor_domainstate(data, stat, event=""):
try:
self.domain_state = data.decode('ascii')
except AttributeError:
self.domain_state = 'unknown'
# toggle state management of this node
if self.name == self.this_node:
if self.domain_state == 'flush' and self.inflush == False:
# Do flushing in a thread so it doesn't block the migrates out
flush_thread = threading.Thread(target=self.flush, args=(), kwargs={})
flush_thread.start()
if self.domain_state == 'unflush' and self.inflush == False:
self.unflush()
@zk_conn.DataWatch('/nodes/{}/memfree'.format(self.name))
def watch_hypervisor_memfree(data, stat, event=""):
try:
self.memfree = data.decode('ascii')
except AttributeError:
self.memfree = 0
@zk_conn.DataWatch('/nodes/{}/memused'.format(self.name))
def watch_hypervisor_memused(data, stat, event=""):
try:
self.memused = data.decode('ascii')
except AttributeError:
self.memused = 0
@zk_conn.DataWatch('/nodes/{}/memalloc'.format(self.name))
def watch_hypervisor_memalloc(data, stat, event=""):
try:
self.memalloc = data.decode('ascii')
except AttributeError:
self.memalloc = 0
@zk_conn.DataWatch('/nodes/{}/vcpualloc'.format(self.name))
def watch_hypervisor_vcpualloc(data, stat, event=""):
try:
self.vcpualloc = data.decode('ascii')
except AttributeError:
self.vcpualloc = 0
@zk_conn.DataWatch('/nodes/{}/runningdomains'.format(self.name))
def watch_hypervisor_runningdomains(data, stat, event=""):
try:
self.domain_list = data.decode('ascii').split()
except AttributeError:
self.domain_list = []
@zk_conn.DataWatch('/nodes/{}/domainscount'.format(self.name))
def watch_hypervisor_domainscount(data, stat, event=""):
try:
self.domains_count = data.decode('ascii')
except AttributeError:
self.domains_count = 0
# Get value functions
def getfreemem(self):
return self.memfree
def getallocmem(self):
return self.memalloc
def getallocvcpu(self):
return self.vcpualloc
def getcpuload(self):
return self.cpuload
def getname(self):
return self.name
def getdaemonstate(self):
return self.daemon_state
def getdomainstate(self):
return self.domain_state
def getdomainlist(self):
return self.domain_list
# Update value functions
def updatenodelist(self, t_node):
self.t_node = t_node
def updatedomainlist(self, s_domain):
self.s_domain = s_domain
# Flush all VMs on the host
def flush(self):
self.inflush = True
ansiiprint.echo('Flushing node "{}" of running VMs'.format(self.name), '', 'i')
ansiiprint.echo('Domain list: {}'.format(', '.join(self.domain_list)), '', 'c')
fixed_domain_list = self.domain_list.copy()
for dom_uuid in fixed_domain_list:
ansiiprint.echo('Selecting target to migrate VM "{}"'.format(dom_uuid), '', 'i')
current_hypervisor = zkhandler.readdata(self.zk_conn, '/domains/{}/hypervisor'.format(dom_uuid))
target_hypervisor = findTargetHypervisor(self.zk_conn, 'mem', dom_uuid)
if target_hypervisor == None:
ansiiprint.echo('Failed to find migration target for VM "{}"; shutting down'.format(dom_uuid), '', 'e')
zkhandler.writedata(self.zk_conn, { '/domains/{}/state'.format(dom_uuid): 'shutdown' })
else:
ansiiprint.echo('Migrating VM "{}" to hypervisor "{}"'.format(dom_uuid, target_hypervisor), '', 'i')
zkhandler.writedata(self.zk_conn, {
'/domains/{}/state'.format(dom_uuid): 'migrate',
'/domains/{}/hypervisor'.format(dom_uuid): target_hypervisor,
'/domains/{}/lasthypervisor'.format(dom_uuid): current_hypervisor
})
# Wait for the VM to migrate so the next VM's free RAM count is accurate (they migrate in serial anyways)
while True:
time.sleep(1)
vm_current_state = zkhandler.readdata(self.zk_conn, '/domains/{}/state'.format(dom_uuid))
if vm_current_state == "start":
break
zkhandler.writedata(self.zk_conn, { '/nodes/{}/runningdomains'.format(self.name): '' })
zkhandler.writedata(self.zk_conn, { '/nodes/{}/domainstate'.format(self.name): 'flushed' })
self.inflush = False
def unflush(self):
self.inflush = True
ansiiprint.echo('Restoring node {} to active service.'.format(self.name), '', 'i')
zkhandler.writedata(self.zk_conn, { '/nodes/{}/domainstate'.format(self.name): 'ready' })
fixed_domain_list = self.s_domain.copy()
for dom_uuid in fixed_domain_list:
try:
last_hypervisor = zkhandler.readdata(self.zk_conn, '/domains/{}/lasthypervisor'.format(dom_uuid))
except:
continue
if last_hypervisor != self.name:
continue
ansiiprint.echo('Setting unmigration for VM "{}"'.format(dom_uuid), '', 'i')
zkhandler.writedata(self.zk_conn, {
'/domains/{}/state'.format(dom_uuid): 'migrate',
'/domains/{}/hypervisor'.format(dom_uuid): self.name,
'/domains/{}/lasthypervisor'.format(dom_uuid): ''
})
self.inflush = False
def update_zookeeper(self):
# Connect to libvirt
libvirt_name = "qemu:///system"
lv_conn = libvirt.open(libvirt_name)
if lv_conn == None:
ansiiprint.echo('Failed to open connection to "{}"'.format(libvirt_name), '', 'e')
return
# Get past state and update if needed
past_state = zkhandler.readdata(self.zk_conn, '/nodes/{}/daemonstate'.format(self.name))
if past_state != 'run':
self.daemon_state = 'run'
zkhandler.writedata(self.zk_conn, { '/nodes/{}/daemonstate'.format(self.name): 'run' })
else:
self.daemon_state = 'run'
# Toggle state management of dead VMs to restart them
memalloc = 0
vcpualloc = 0
for domain, instance in self.s_domain.items():
if instance.inshutdown == False and domain in self.domain_list:
# Add the allocated memory to our memalloc value
memalloc += instance.getmemory()
vcpualloc += instance.getvcpus()
if instance.getstate() == 'start' and instance.gethypervisor() == self.name:
if instance.getdom() != None:
try:
if instance.getdom().state()[0] != libvirt.VIR_DOMAIN_RUNNING:
raise
except Exception as e:
# Toggle a state "change"
zkhandler.writedata(self.zk_conn, { '/domains/{}/state'.format(domain): instance.getstate() })
# Ensure that any running VMs are readded to the domain_list
running_domains = lv_conn.listAllDomains(libvirt.VIR_CONNECT_LIST_DOMAINS_ACTIVE)
for domain in running_domains:
domain_uuid = domain.UUIDString()
if domain_uuid not in self.domain_list:
self.domain_list.append(domain_uuid)
# Set our information in zookeeper
self.name = lv_conn.getHostname()
self.memused = int(psutil.virtual_memory().used / 1024 / 1024)
self.memfree = int(psutil.virtual_memory().free / 1024 / 1024)
self.memalloc = memalloc
self.vcpualloc = vcpualloc
self.cpuload = os.getloadavg()[0]
self.domains_count = len(lv_conn.listDomainsID())
keepalive_time = int(time.time())
try:
zkhandler.writedata(self.zk_conn, {
'/nodes/{}/memused'.format(self.name): str(self.memused),
'/nodes/{}/memfree'.format(self.name): str(self.memfree),
'/nodes/{}/memalloc'.format(self.name): str(self.memalloc),
'/nodes/{}/vcpualloc'.format(self.name): str(self.vcpualloc),
'/nodes/{}/cpuload'.format(self.name): str(self.cpuload),
'/nodes/{}/runningdomains'.format(self.name): ' '.join(self.domain_list),
'/nodes/{}/domainscount'.format(self.name): str(self.domains_count),
'/nodes/{}/keepalive'.format(self.name): str(keepalive_time)
})
except:
ansiiprint.echo('Failed to set keepalive data', '', 'e')
return
# Close the Libvirt connection
lv_conn.close()
# Display node information to the terminal
ansiiprint.echo('{}{} keepalive{}'.format(ansiiprint.purple(), self.name, ansiiprint.end()), '', 't')
ansiiprint.echo('{0}Active domains:{1} {2} {0}Allocated memory [MiB]:{1} {6} {0}Free memory [MiB]:{1} {3} {0}Used memory [MiB]:{1} {4} {0}Load:{1} {5}'.format(ansiiprint.bold(), ansiiprint.end(), self.domains_count, self.memfree, self.memused, self.cpuload, self.memalloc), '', 'c')
# Update our local node lists
for node_name in self.t_node:
try:
node_daemon_state = zkhandler.readdata(self.zk_conn, '/nodes/{}/daemonstate'.format(node_name))
node_domain_state = zkhandler.readdata(self.zk_conn, '/nodes/{}/domainstate'.format(node_name))
node_keepalive = int(zkhandler.readdata(self.zk_conn, '/nodes/{}/keepalive'.format(node_name)))
except:
node_daemon_state = 'unknown'
node_domain_state = 'unknown'
node_keepalive = 0
# Handle deadtime and fencng if needed
# (A node is considered dead when its keepalive timer is >6*keepalive_interval seconds
# out-of-date while in 'start' state)
node_deadtime = int(time.time()) - ( int(self.config['keepalive_interval']) * int(self.config['fence_intervals']) )
if node_keepalive < node_deadtime and node_daemon_state == 'run':
ansiiprint.echo('Node {} seems dead - starting monitor for fencing'.format(node_name), '', 'w')
zkhandler.writedata(self.zk_conn, { '/nodes/{}/daemonstate'.format(node_name): 'dead' })
fence_thread = threading.Thread(target=fenceNode, args=(node_name, self.zk_conn, self.config), kwargs={})
fence_thread.start()
# Update the arrays
if node_daemon_state == 'run' and node_domain_state != 'flushed' and node_name not in self.active_node_list:
self.active_node_list.append(node_name)
try:
self.flushed_node_list.remove(node_name)
except ValueError:
pass
try:
self.inactive_node_list.remove(node_name)
except ValueError:
pass
if node_daemon_state != 'run' and node_domain_state != 'flushed' and node_name not in self.inactive_node_list:
self.inactive_node_list.append(node_name)
try:
self.active_node_list.remove(node_name)
except ValueError:
pass
try:
self.flushed_node_list.remove(node_name)
except ValueError:
pass
if node_domain_state == 'flushed' and node_name not in self.flushed_node_list:
self.flushed_node_list.append(node_name)
try:
self.active_node_list.remove(node_name)
except ValueError:
pass
try:
self.inactive_node_list.remove(node_name)
except ValueError:
pass
# Display cluster information to the terminal
ansiiprint.echo('{}Cluster status{}'.format(ansiiprint.purple(), ansiiprint.end()), '', 't')
ansiiprint.echo('{}Active nodes:{} {}'.format(ansiiprint.bold(), ansiiprint.end(), ' '.join(self.active_node_list)), '', 'c')
ansiiprint.echo('{}Inactive nodes:{} {}'.format(ansiiprint.bold(), ansiiprint.end(), ' '.join(self.inactive_node_list)), '', 'c')
ansiiprint.echo('{}Flushed nodes:{} {}'.format(ansiiprint.bold(), ansiiprint.end(), ' '.join(self.flushed_node_list)), '', 'c')
#
# Find a migration target
#
def findTargetHypervisor(zk_conn, search_field, dom_uuid):
if search_field == 'mem':
return findTargetHypervisorMem(zk_conn, dom_uuid)
if search_field == 'load':
return findTargetHypervisorLoad(zk_conn, dom_uuid)
if search_field == 'vcpus':
return findTargetHypervisorVCPUs(zk_conn, dom_uuid)
if search_field == 'vms':
return findTargetHypervisorVMs(zk_conn, dom_uuid)
return None
# Get the list of valid target hypervisors
def getHypervisors(zk_conn, dom_uuid):
valid_hypervisor_list = []
full_hypervisor_list = zkhandler.listchildren(zk_conn, '/nodes')
current_hypervisor = zkhandler.readdata(zk_conn, '/domains/{}/hypervisor'.format(dom_uuid))
for hypervisor in full_hypervisor_list:
daemon_state = zkhandler.readdata(zk_conn, '/nodes/{}/daemonstate'.format(hypervisor))
domain_state = zkhandler.readdata(zk_conn, '/nodes/{}/domainstate'.format(hypervisor))
if hypervisor == current_hypervisor:
continue
if daemon_state != 'run' or domain_state != 'ready':
continue
valid_hypervisor_list.append(hypervisor)
return full_hypervisor_list
# via free memory (relative to allocated memory)
def findTargetHypervisorMem(zk_conn, dom_uuid):
most_allocfree = 0
target_hypervisor = None
hypervisor_list = getHypervisors(zk_conn, dom_uuid)
for hypervisor in hypervisor_list:
memalloc = int(zkhandler.readdata(zk_conn, '/nodes/{}/memalloc'.format(hypervisor)))
memused = int(zkhandler.readdata(zk_conn, '/nodes/{}/memused'.format(hypervisor)))
memfree = int(zkhandler.readdata(zk_conn, '/nodes/{}/memfree'.format(hypervisor)))
memtotal = memused + memfree
allocfree = memtotal - memalloc
if allocfree > most_allocfree:
most_allocfree = allocfree
target_hypervisor = hypervisor
return target_hypervisor
# via load average
def findTargetHypervisorLoad(zk_conn, dom_uuid):
least_load = 9999
target_hypervisor = None
hypervisor_list = getHypervisors(zk_conn, dom_uuid)
for hypervisor in hypervisor_list:
load = int(zkhandler.readdata(zk_conn, '/nodes/{}/load'.format(hypervisor)))
if load < least_load:
least_load = load
target_hypevisor = hypervisor
return target_hypervisor
# via total vCPUs
def findTargetHypervisorVCPUs(zk_conn, dom_uuid):
least_vcpus = 9999
target_hypervisor = None
hypervisor_list = getHypervisors(zk_conn, dom_uuid)
for hypervisor in hypervisor_list:
vcpus = int(zkhandler.readdata(zk_conn, '/nodes/{}/vcpualloc'.format(hypervisor)))
if vcpus < least_vcpus:
least_vcpus = vcpus
target_hypervisor = hypervisor
return target_hypervisor
# via total VMs
def findTargetHypervisorVMs(zk_conn, dom_uuid):
least_vms = 9999
target_hypervisor = None
hypervisor_list = getHypervisors(zk_conn, dom_uuid)
for hypervisor in hypervisor_list:
vms = int(zkhandler.readdata(zk_conn, '/nodes/{}/domainscount'.format(hypervisor)))
if vms < least_vms:
least_vms = vms
target_hypervisor = hypervisor
return target_hypervisor
#
# Fence thread entry function
#
def fenceNode(node_name, zk_conn, config):
failcount = 0
# We allow exactly 3 saving throws for the host to come back online
while failcount < 3:
# Wait 5 seconds
time.sleep(5)
# Get the state
node_daemon_state = zkhandler.readdata(zk_conn, '/nodes/{}/daemonstate'.format(node_name))
# Is it still 'dead'
if node_daemon_state == 'dead':
failcount += 1
ansiiprint.echo('Node "{}" failed {} saving throws'.format(node_name, failcount), '', 'w')
# It changed back to something else so it must be alive
else:
ansiiprint.echo('Node "{}" passed a saving throw; canceling fence'.format(node_name), '', 'o')
return
ansiiprint.echo('Fencing node "{}" via IPMI reboot signal'.format(node_name), '', 'e')
# Get IPMI information
ipmi_hostname = zkhandler.readdata(zk_conn, '/nodes/{}/ipmihostname'.format(node_name))
ipmi_username = zkhandler.readdata(zk_conn, '/nodes/{}/ipmiusername'.format(node_name))
ipmi_password = zkhandler.readdata(zk_conn, '/nodes/{}/ipmipassword'.format(node_name))
# Shoot it in the head
fence_status = rebootViaIPMI(ipmi_hostname, ipmi_username, ipmi_password)
# Hold to ensure the fence takes effect
time.sleep(3)
# If the fence succeeded and successful_fence is migrate
if fence_status == True and config['successful_fence'] == 'migrate':
migrateFromFencedHost(zk_conn, node_name)
# If the fence failed and failed_fence is migrate
if fence_status == False and config['failed_fence'] == 'migrate' and config['suicide_intervals'] != '0':
migrateFromFencedHost(zk_conn, node_name)
# Migrate hosts away from a fenced node
def migrateFromFencedHost(zk_conn, node_name):
ansiiprint.echo('Moving VMs from dead hypervisor "{}" to new hosts'.format(node_name), '', 'i')
dead_node_running_domains = zkhandler.readdata(zk_conn, '/nodes/{}/runningdomains'.format(node_name)).split()
for dom_uuid in dead_node_running_domains:
target_hypervisor = findTargetHypervisor(zk_conn, 'mem', dom_uuid)
ansiiprint.echo('Moving VM "{}" to hypervisor "{}"'.format(dom_uuid, target_hypervisor), '', 'i')
zkhandler.writedata(zk_conn, {
'/domains/{}/state'.format(dom_uuid): 'start',
'/domains/{}/hypervisor'.format(dom_uuid): target_hypervisor,
'/domains/{}/lasthypervisor'.format(dom_uuid): current_hypervisor
})
# Set node in flushed state for easy remigrating when it comes back
zkhandler.writedata(zk_conn, { '/nodes/{}/domainstate'.format(node_name): 'flushed' })
#
# Perform an IPMI fence
#
def rebootViaIPMI(ipmi_hostname, ipmi_user, ipmi_password):
ipmi_command = ['/usr/bin/ipmitool', '-I', 'lanplus', '-H', ipmi_hostname, '-U', ipmi_user, '-P', ipmi_password, 'chassis', 'power', 'reset']
ipmi_command_output = subprocess.run(ipmi_command, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
if ipmi_command_output.returncode == 0:
ansiiprint.echo('Successfully rebooted dead node', '', 'o')
return True
else:
ansiiprint.echo('Failed to reboot dead node', '', 'e')
return False