HACluster refactoring

TODO

@@ -15,23 +15,13 @@ HA Cluster (pacemaker/corosync)  Charm
  * TODO: Fix Disable upstart jobs
    - sudo sh -c "echo 'manual' > /etc/init/SERVICE.override"
 
- * BIG PROBlEM:
-   - given that we can only deploy hacluster once, and its config defines
-     the corosync configuration options, then we need to change the approach
-     on how the corosync is defined. Possible solution:
-     - in the 'service/charm' that uses hacluster, it will define the corosync options
-     - Instead of network source, it can define interfaces to use and assume each ethX
-       interface is connected to the same network and autodetect the network address.
- * TODO: on juju destroy-server quantum, ha-relation-broken is executed.
-   we need to put nodes in standby or delete them.
-
- * ERROR/BUG (discuss with jamespage):
-   - On add-unit in controller environment:
-     - subordinate (in added unit) gets the relation data in ha-relation-joined
-   - On add-unit in openstack
-     - subordinate (in added unit) *DOESN'T* get the the relation data in ha-relation-joined
-       - This is fine really cause we don't really need to re-add the services.
-       - However, the problem is that upstart jobs don't get stopped.
-
   update-rc.d -f pacemaker remove
   update-rc.d pacemaker start 50 1 2 3 4 5 . stop 01 0 6 .
+
+TODO: Problem seems to be that peer-relation gets executed before the subordinate relation.
+
+In that case, peer relation would have to put nodes in standby and then the subordinate relation
+will have to put the nodes online and configure the services. Or probably not use it at all.
+
+Hanode-relation puts node in standby.
+ha-relation counts nodes in hanode-relation and if >2 then we online them and setup cluster.

config.yaml

@@ -1,9 +1,4 @@
 options:
-  corosync_bindnetaddr:
-    type: string
-    description: |
-      Network address of the interface on which corosync will communicate
-      with the other nodes of the cluster.
   corosync_mcastaddr:
     default: 226.94.1.1
     type: string
@@ -11,13 +6,6 @@ options:
       Multicast IP address to use for exchanging messages over the network.
       If multiple clusters are on the same bindnetaddr network, this value
       can be changed.
-  corosync_mcastport:
-    default: 5405
-    type: int
-    description: |
-      Multicast Port number to use for exchanging messages. If multiple
-      clusters sit on the same Multicast IP Address, this value needs to
-      be changed.
   corosync_pcmk_ver:
     default: 1
     type: int
@@ -26,6 +14,7 @@ options:
       Corosync how to start pacemaker
   corosync_key:
     type: string
+    default: corosync-key
     description: |
       This value will become the Corosync authentication key. To generate
       a suitable value use:

hooks/hanode-relation-joined

@@ -0,0 +1 @@
+hooks.py

hooks/hooks.py

@@ -21,27 +21,42 @@ import pcmk
 def install():
     utils.juju_log('INFO', 'Begin install hook.')
     utils.configure_source()
-    utils.install('corosync', 'pacemaker', 'openstack-resource-agents')
+    utils.install('corosync', 'pacemaker', 'openstack-resource-agents', 'python-netaddr')
     utils.juju_log('INFO', 'End install hook.')
 
 
+def get_corosync_conf():
+    for relid in utils.relation_ids('ha'):
+        for unit in utils.relation_list(relid):
+            conf = {
+                'corosync_bindnetaddr': utils.get_network_address(
+                                          utils.relation_get('corosync_bindiface',
+                                          unit, relid)),
+                'corosync_mcastport': utils.relation_get('corosync_mcastport',
+                                        unit, relid),
+                'corosync_mcastaddr': utils.config_get('corosync_mcastaddr'),
+                'corosync_pcmk_ver': utils.config_get('corosync_pcmk_ver'),
+                }
+            if None not in conf.itervalues():
+                return conf
+    return None
+
+
 def emit_corosync_conf():
     # read config variables
-    corosync_conf_context = {
-        'corosync_bindnetaddr': utils.config_get('corosync_bindnetaddr'),
-        'corosync_mcastaddr': utils.config_get('corosync_mcastaddr'),
-        'corosync_mcastport': utils.config_get('corosync_mcastport'),
-        'corosync_pcmk_ver': utils.config_get('corosync_pcmk_ver'),
-        }
-
-    # write /etc/default/corosync file
-    with open('/etc/default/corosync', 'w') as corosync_default:
-        corosync_default.write(utils.render_template('corosync', corosync_conf_context))
+    corosync_conf_context = get_corosync_conf()
 
     # write config file (/etc/corosync/corosync.conf
     with open('/etc/corosync/corosync.conf', 'w') as corosync_conf:
         corosync_conf.write(utils.render_template('corosync.conf', corosync_conf_context))
 
+
+def emit_base_conf():
+    corosync_default_context = {'corosync_enabled': 'yes'}
+    # write /etc/default/corosync file
+    with open('/etc/default/corosync', 'w') as corosync_default:
+        corosync_default.write(utils.render_template('corosync', corosync_default_context))
+
     # write the authkey
     corosync_key=utils.config_get('corosync_key')
     with open(corosync_key, 'w') as corosync_key_file:
@@ -51,12 +66,6 @@ def emit_corosync_conf():
 def config_changed():
     utils.juju_log('INFO', 'Begin config-changed hook.')
 
-    # validate configuration options
-    corosync_bindnetaddr = utils.config_get('corosync_bindnetaddr')
-    if corosync_bindnetaddr == '':
-        utils.juju_log('CRITICAL', 'No bindnetaddr supplied, cannot proceed.')
-        sys.exit(1)
-
     corosync_key = utils.config_get('corosync_key')
     if corosync_key == '':
         utils.juju_log('CRITICAL',
@@ -64,7 +73,7 @@ def config_changed():
         sys.exit(1)
 
     # Create a new config file
-    emit_corosync_conf()
+    emit_base_conf()
 
     utils.juju_log('INFO', 'End config-changed hook.')
 
@@ -81,14 +90,15 @@ def start():
     else:
         utils.start("corosync")
 
-    # TODO: Only start pacemaker after making sure
+    # Only start pacemaker after making sure
     # corosync has been started
     # Wait a few seconds for corosync to start.
     time.sleep(2)
-    if utils.running("pacemaker"):
-        utils.restart("pacemaker")
-    else:
-        utils.start("pacemaker")
+    if utils.running("corosync"):
+        if utils.running("pacemaker"):
+            utils.restart("pacemaker")
+        else:
+            utils.start("pacemaker")
 
 
 def stop():
@@ -100,14 +110,23 @@ def stop():
 def ha_relation():
     utils.juju_log('INFO', 'Begin ha relation joined/changed hook')
 
-    pcmk.wait_for_pcmk()
+    if utils.relation_get("corosync_bindiface") is None:
+        return
+    elif utils.relation_get("corosync_mcastport") is None:
+        return
+    else:
+        emit_corosync_conf()
+        utils.restart("corosync")
+        time.sleep(2)
+        utils.restart("pacemaker")
 
-    cmd = "crm configure property stonith-enabled=false"
-    pcmk.commit(cmd)
-    cmd = "crm configure property no-quorum-policy=ignore"
-    pcmk.commit(cmd)
-    cmd = 'crm configure rsc_defaults $id="rsc-options" resource-stickiness="100"'
-    pcmk.commit(cmd)
+    # Check that there's enough nodes in order to perform the
+    # configuration of the HA cluster
+    if len(get_cluster_nodes()) < 2:
+        return
+    else:
+        utils.juju_log('INFO', 'hanode-relation: Waiting for PCMK to start')
+        pcmk.wait_for_pcmk()
 
     # Obtain relation information
     import ast
@@ -120,6 +139,7 @@ def ha_relation():
     init_services = {} if utils.relation_get("init_services") is None else ast.literal_eval(utils.relation_get("init_services"))
 
     # Configuring the Resource
+    utils.juju_log('INFO', 'ha-relation: Configuring Resources')
     for res_name,res_type in resources.iteritems():
         # disable the service we are going to put in HA
         if res_type.split(':')[0] == "lsb":
@@ -131,7 +151,8 @@ def ha_relation():
             if utils.running(init_services[res_name]):
                 utils.stop(init_services[res_name])
         # Put the services in HA, if not already done so
-        if not pcmk.is_resource_present(res_name):
+        #if not pcmk.is_resource_present(res_name):
+        if not pcmk.crm_opt_exists(res_name):
             if resource_params[res_name] is None:
                 cmd = 'crm -F configure primitive %s %s' % (res_name, res_type)
             else:
@@ -140,28 +161,45 @@ def ha_relation():
             utils.juju_log('INFO', '%s' % cmd)
 
     # Configuring groups
+    utils.juju_log('INFO', 'ha-relation: Configuring Groups')
     for grp_name, grp_params in groups.iteritems():
-        cmd = 'crm -F configure group %s %s' % (grp_name, grp_params)
-        pcmk.commit(cmd)
-        utils.juju_log('INFO', '%s' % cmd)
+        if not pcmk.crm_opt_exists(grp_name):
+            cmd = 'crm -F configure group %s %s' % (grp_name, grp_params)
+            pcmk.commit(cmd)
+            utils.juju_log('INFO', '%s' % cmd)
 
     # Configuring ordering
+    utils.juju_log('INFO', 'ha-relation: Configuring Orders')
     for ord_name, ord_params in orders.iteritems():
-        cmd = 'crm -F configure order %s %s' % (ord_name, ord_params)
-        pcmk.commit(cmd)
-        utils.juju_log('INFO', '%s' % cmd)
+        if not pcmk.crm_opt_exists(ord_name):
+            cmd = 'crm -F configure order %s %s' % (ord_name, ord_params)
+            pcmk.commit(cmd)
+            utils.juju_log('INFO', '%s' % cmd)
 
     # Configuring colocations
+    utils.juju_log('INFO', 'ha-relation: Configuring Colocations')
     for col_name, col_params in colocations.iteritems():
-        cmd = 'crm -F configure colocation %s %s' % (col_name, col_params)
-        pcmk.commit(cmd)
-        utils.juju_log('INFO', '%s' % cmd)
+        if not pcmk.crm_opt_exists(col_name):
+            cmd = 'crm -F configure colocation %s %s' % (col_name, col_params)
+            pcmk.commit(cmd)
+            utils.juju_log('INFO', '%s' % cmd)
 
     # Configuring clones
+    utils.juju_log('INFO', 'ha-relation: Configuring Clones')
     for cln_name, cln_params in clones.iteritems():
-        cmd = 'crm -F configure clone %s %s' % (cln_name, cln_params)
-        pcmk.commit(cmd)
-        utils.juju_log('INFO', '%s' % cmd)
+        if not pcmk.crm_opt_exists(cln_name):
+            cmd = 'crm -F configure clone %s %s' % (cln_name, cln_params)
+            pcmk.commit(cmd)
+            utils.juju_log('INFO', '%s' % cmd)
+
+    for res_name,res_type in resources.iteritems():
+        # TODO: This should first check that the resources is running
+        if len(init_services) != 0 and res_name in init_services:
+            # If the resource is in HA already, and it is a service, restart
+            # the pcmk resource as the config file might have changed by the
+            # principal charm
+            cmd = 'crm resource restart %s' % res_name
+            pcmk.commit(cmd)
 
     utils.juju_log('INFO', 'End ha relation joined/changed hook')
 
@@ -171,19 +209,50 @@ def ha_relation_departed():
     # If this happens, and a new relation is created in the same machine
     # (which already has node), then check whether it is standby and put it
     # in online mode. This should be done in ha_relation_joined.
-    cmd = "crm -F node standby %s" % utils.get_unit_hostname()
-    pcmk.commit(cmd)
+    pcmk.standby(utils.get_unit_hostname())
+
+
+def get_cluster_nodes():
+    hosts = []
+    hosts.append('{}:6789'.format(utils.get_host_ip()))
+
+    for relid in utils.relation_ids('hanode'):
+        for unit in utils.relation_list(relid):
+            hosts.append(
+                '{}:6789'.format(utils.get_host_ip(
+                                    utils.relation_get('private-address',
+                                                       unit, relid)))
+                )
+
+    hosts.sort()
+    return hosts
+
+
+def hanode_relation():
+    utils.juju_log('INFO', 'Begin hanode peer relation hook')
+    if len(get_cluster_nodes()) >= 2:
+        utils.juju_log('INFO', 'hanode-relation: Waiting for PCMK to start')
+        pcmk.wait_for_pcmk()
+
+        utils.juju_log('INFO', 'hanode-relation: Doing global configuration')
+        cmd = "crm configure property stonith-enabled=false"
+        pcmk.commit(cmd)
+        cmd = "crm configure property no-quorum-policy=ignore"
+        pcmk.commit(cmd)
+        cmd = 'crm configure rsc_defaults $id="rsc-options" resource-stickiness="100"'
+        pcmk.commit(cmd)
 
 
 utils.do_hooks({
-        'config-changed': config_changed,
         'install': install,
+        'config-changed': config_changed,
         'start': start,
         'stop': stop,
         'upgrade-charm': upgrade_charm,
         'ha-relation-joined': ha_relation,
         'ha-relation-changed': ha_relation,
         'ha-relation-departed': ha_relation_departed,
+        'hanode-relation-joined': hanode_relation,
         #'hanode-relation-departed': hanode_relation_departed, # TODO: should probably remove nodes from the cluster
         })
 

hooks/pcmk.py

@@ -20,12 +20,33 @@ def commit(cmd):
     subprocess.call(cmd.split())
 
 
-#def wait_for_cluster():
-#    while (not is_running()):
-#        time.sleep(3)
-
 def is_resource_present(resource):
     (status, output) = commands.getstatusoutput("crm resource status %s" % resource)
     if status != 0:
         return False
     return True
+
+
+def standby(node=None):
+    if node is None:
+        cmd = "crm -F node standby"
+    else:
+        cmd = "crm -F node standby %s" % node
+    commit(cmd)
+
+
+def online(node=None):
+    if node is None:
+        cmd = "crm -F node online"
+    else:
+        cmd = "crm -F node online %s" % node
+    commit(cmd)
+
+
+def crm_opt_exists(opt_name):
+     (status, output) = commands.getstatusoutput("crm configure show")
+     show_re = re.compile(opt_name)
+     opt = show_re.search(output)
+     if opt:
+         return True
+     return False

hooks/utils.py

@@ -13,6 +13,8 @@ import re
 import subprocess
 import socket
 import sys
+import fcntl
+import struct
 
 
 def do_hooks(hooks):
@@ -43,6 +45,12 @@ except ImportError:
     install('python-jinja2')
     import jinja2
 
+try:
+    from netaddr import *
+except:
+    install('python-netaddr')
+    from netaddr import *
+
 
 def render_template(template_name, context, template_dir=TEMPLATES_DIR):
     templates = jinja2.Environment(
@@ -223,3 +231,35 @@ def disable_lsb_services(*services):
 def enable_lsb_services(*services):
     for service in services:
         subprocess.call(['update-rc.d','-f',service,'defaults'])
+
+
+def get_iface_ipaddr(iface):
+    s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+    return socket.inet_ntoa(fcntl.ioctl(
+        s.fileno(),
+        0x8919,  # SIOCGIFADDR
+        struct.pack('256s', iface[:15])
+    )[20:24])
+
+
+def get_iface_netmask(iface):
+    s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+    return socket.inet_ntoa(fcntl.ioctl(
+        s.fileno(),
+        0x891b, # SIOCGIFNETMASK
+        struct.pack('256s', iface[:15])
+    )[20:24])
+
+
+def get_netmask_cidr(netmask):
+    netmask = netmask.split('.')
+    binary_str = ''
+    for octet in netmask:
+        binary_str += bin(int(octet))[2:].zfill(8)
+    return str(len(binary_str.rstrip('0')))
+
+
+def get_network_address(iface):
+    network = "%s/%s" % (get_iface_ipaddr(iface), get_netmask_cidr(get_iface_netmask(iface)))
+    ip = IPNetwork(network)
+    return str(ip.network)

templates/corosync

@@ -1,3 +1,3 @@
 # Configuration file created by the ha charm
 # start corosync at boot [yes|no]
-START=yes
+START={{ corosync_enabled }}