Move Zookeeper update out of NodeInstance and into the main Daemon

node-daemon/pvcd/fencing.py

@@ -0,0 +1,107 @@
+#!/usr/bin/env python3
+
+# fencing.py - PVC daemon function library, node fencing functions
+# 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 threading
+import time
+import threading
+
+import pvcd.zkhandler as zkhandler
+import pvcd.common as common
+
+#
+# Fence thread entry function
+#
+def fenceNode(node_name, zk_conn, config, logger):
+    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
+            logger.out('Node "{}" failed {} saving throws'.format(node_name, failcount), state='w')
+        # It changed back to something else so it must be alive
+        else:
+            logger.out('Node "{}" passed a saving throw; canceling fence'.format(node_name), state='o')
+            return
+
+    logger.out('Fencing node "{}" via IPMI reboot signal'.format(node_name), state='w')
+
+    # 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, logger)
+    # Hold to ensure the fence takes effect
+    time.sleep(3)
+
+    # Force into secondary network state if needed
+    if node_name in config['coordinators'].split(','):
+        zkhandler.writedata(zk_conn, { '/nodes/{}/routerstate'.format(node_name): 'secondary' })
+        if zkhandler.readdata(zk_conn, '/primary_node') == node_name:
+            zkhandler.writedata(zk_conn, { '/primary_node': 'none' })
+        
+    # If the fence succeeded and successful_fence is migrate
+    if fence_status == True and config['successful_fence'] == 'migrate':
+        migrateFromFencedNode(zk_conn, node_name, logger)
+
+    # If the fence failed and failed_fence is migrate
+    if fence_status == False and config['failed_fence'] == 'migrate' and config['suicide_intervals'] != '0':
+        migrateFromFencedNode(zk_conn, node_name, logger)
+
+# Migrate hosts away from a fenced node
+def migrateFromFencedNode(zk_conn, node_name, logger):
+    logger.out('Moving VMs from dead node "{}" to new hosts'.format(node_name), state='i')
+    dead_node_running_domains = zkhandler.readdata(zk_conn, '/nodes/{}/runningdomains'.format(node_name)).split()
+    for dom_uuid in dead_node_running_domains:
+        target_node = findTargetHypervisor(zk_conn, 'mem', dom_uuid)
+
+        logger.out('Moving VM "{}" to node "{}"'.format(dom_uuid, target_node), state='i')
+        zkhandler.writedata(zk_conn, {
+            '/domains/{}/state'.format(dom_uuid): 'start',
+            '/domains/{}/node'.format(dom_uuid): target_node,
+            '/domains/{}/lastnode'.format(dom_uuid): node_name
+        })
+
+    # 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, logger):
+    ipmi_command = ['/usr/bin/ipmitool', '-I', 'lanplus', '-H', ipmi_hostname, '-U', ipmi_user, '-P', ipmi_password, 'chassis', 'power', 'reset']
+    ipmi_command = '/usr/bin/ipmitool -I lanplus -H {} -U {} -P {} chassis power reset'.format(
+        ipmi_hostname, ipmi_user, ipmi_password
+    )
+    ipmi_command_retcode, ipmi_command_stdout, ipmi_command_stderr = common.run_os_command(ipmi_command)
+    if ipmi_command_retcode == 0:
+        logger.out('Successfully rebooted dead node', state='o')
+        return True
+    else:
+        logger.out('Failed to reboot dead node', state='e')
+        return False