Merge lp:~brad-marshall/charms/trusty/nova-cloud-controller/add-nrpe-checks into lp:~openstack-charmers-archive/charms/trusty/nova-cloud-controller/trunk

[Brad Marshall]

Adds nrpe-external-master interface and adds basic nrpe checks.

[Ryan Beisner (1chb1n)]

UOSCI bot says:
charm_lint_check #997 trusty-nova-cloud-controller for brad-marshall mp241489
    LINT FAIL: lint-test failed

LINT Results (max last 5 lines):
  hooks/nova_cc_hooks.py:857:80: E501 line too long (92 > 79 characters)
  hooks/nova_cc_hooks.py:887:22: E251 unexpected spaces around keyword / parameter equals
  hooks/nova_cc_hooks.py:887:24: E251 unexpected spaces around keyword / parameter equals
  hooks/nova_cc_hooks.py:892:1: E302 expected 2 blank lines, found 1
  make: *** [lint] Error 1

Full lint test output: http://paste.ubuntu.com/8955797/
Build: http://10.98.191.181:8080/job/charm_lint_check/997/

[Ryan Beisner (1chb1n)]

UOSCI bot says:
charm_unit_test #832 trusty-nova-cloud-controller for brad-marshall mp241489
    UNIT FAIL: unit-test failed

UNIT Results (max last 5 lines):
  TOTAL 1061 380 64%
  Ran 96 tests in 10.348s
  FAILED (errors=2)
  mERROR:root:Make target returned non-zero.
ake: *** [unit_test] Error 1

Full unit test output: http://paste.ubuntu.com/8955811/
Build: http://10.98.191.181:8080/job/charm_unit_test/832/

[Ryan Beisner (1chb1n)]

UOSCI bot says:
charm_amulet_test #377 trusty-nova-cloud-controller for brad-marshall mp241489
    AMULET FAIL: amulet-test failed

AMULET Results (max last 5 lines):
  juju-test.conductor DEBUG : Calling "juju destroy-environment -y osci-sv04"
  WARNING cannot delete security group "juju-osci-sv04-0". Used by another environment?
  juju-test INFO : Results: 1 passed, 2 failed, 0 errored
  ERROR subprocess encountered error code 2
  make: *** [test] Error 2

Full amulet test output: http://paste.ubuntu.com/8955994/
Build: http://10.98.191.181:8080/job/charm_amulet_test/377/

[lp:~brad-marshall/charms/trusty/nova-cloud-controller/add-nrpe-checks]

129. By Brad Marshall on 2014-11-17

[bradm] Add monitoring for sysvinit daemons, use services() instead of hard coded daemon list, pep8 fixes

[uosci-testing-bot (uosci-testing-bot)]

UOSCI bot says:
charm_lint_check #1088 trusty-nova-cloud-controller for brad-marshall mp241489
    LINT FAIL: lint-test failed

LINT Results (max last 5 lines):
  hooks/nova_cc_hooks.py:896:26: E251 unexpected spaces around keyword / parameter equals
  hooks/nova_cc_hooks.py:896:28: E251 unexpected spaces around keyword / parameter equals
  hooks/nova_cc_hooks.py:896:80: E501 line too long (101 > 79 characters)
  hooks/nova_cc_hooks.py:901:1: E302 expected 2 blank lines, found 1
  make: *** [lint] Error 1

Full lint test output: http://paste.ubuntu.com/9052154/
Build: http://10.98.191.181:8080/job/charm_lint_check/1088/

[uosci-testing-bot (uosci-testing-bot)]

UOSCI bot says:
charm_unit_test #922 trusty-nova-cloud-controller for brad-marshall mp241489
    UNIT FAIL: unit-test failed

UNIT Results (max last 5 lines):
  TOTAL 1072 392 63%
  Ran 96 tests in 9.000s
  FAILED (errors=2)
  maERROR:root:Make target returned non-zero.
ke: *** [unit_test] Error 1

Full unit test output: http://paste.ubuntu.com/9052172/
Build: http://10.98.191.181:8080/job/charm_unit_test/922/

[uosci-testing-bot (uosci-testing-bot)]

UOSCI bot says:
charm_amulet_test #430 trusty-nova-cloud-controller for brad-marshall mp241489
    AMULET FAIL: amulet-test failed

AMULET Results (max last 5 lines):
  juju-test.conductor DEBUG : Calling "juju destroy-environment -y osci-sv11"
  WARNING cannot delete security group "juju-osci-sv11-0". Used by another environment?
  juju-test INFO : Results: 1 passed, 2 failed, 0 errored
  ERROR subprocess encountered error code 2
  make: *** [test] Error 2

Full amulet test output: http://paste.ubuntu.com/9052240/
Build: http://10.98.191.181:8080/job/charm_amulet_test/430/

[lp:~brad-marshall/charms/trusty/nova-cloud-controller/add-nrpe-checks]

130. By Brad Marshall on 2014-11-17

[bradm] Removed puppet header from nagios_plugin module

[uosci-testing-bot (uosci-testing-bot)]

UOSCI bot says:
charm_lint_check #1100 trusty-nova-cloud-controller for brad-marshall mp241489
    LINT FAIL: lint-test failed

LINT Results (max last 5 lines):
  hooks/nova_cc_hooks.py:896:26: E251 unexpected spaces around keyword / parameter equals
  hooks/nova_cc_hooks.py:896:28: E251 unexpected spaces around keyword / parameter equals
  hooks/nova_cc_hooks.py:896:80: E501 line too long (101 > 79 characters)
  hooks/nova_cc_hooks.py:901:1: E302 expected 2 blank lines, found 1
  make: *** [lint] Error 1

Full lint test output: http://paste.ubuntu.com/9052991/
Build: http://10.98.191.181:8080/job/charm_lint_check/1100/

[uosci-testing-bot (uosci-testing-bot)]

UOSCI bot says:
charm_unit_test #934 trusty-nova-cloud-controller for brad-marshall mp241489
    UNIT FAIL: unit-test failed

UNIT Results (max last 5 lines):
  TOTAL 1072 392 63%
  Ran 96 tests in 10.146s
  FAILED (errors=2)
  mERROR:root:Make target returned non-zero.
ake: *** [unit_test] Error 1

Full unit test output: http://paste.ubuntu.com/9052999/
Build: http://10.98.191.181:8080/job/charm_unit_test/934/

[uosci-testing-bot (uosci-testing-bot)]

UOSCI bot says:
charm_amulet_test #442 trusty-nova-cloud-controller for brad-marshall mp241489
    AMULET FAIL: amulet-test failed

AMULET Results (max last 5 lines):
  juju-test.conductor DEBUG : Calling "juju destroy-environment -y osci-sv04"
  WARNING cannot delete security group "juju-osci-sv04-0". Used by another environment?
  juju-test INFO : Results: 1 passed, 2 failed, 0 errored
  ERROR subprocess encountered error code 2
  make: *** [test] Error 2

Full amulet test output: http://paste.ubuntu.com/9053036/
Build: http://10.98.191.181:8080/job/charm_amulet_test/442/

[lp:~brad-marshall/charms/trusty/nova-cloud-controller/add-nrpe-checks]

131. By Brad Marshall on 2014-11-18

[bradm] Removed nagios check files that were moved to nrpe-external-master charm

[uosci-testing-bot (uosci-testing-bot)]

UOSCI bot says:
charm_lint_check #1116 trusty-nova-cloud-controller for brad-marshall mp241489
    LINT FAIL: lint-test failed

LINT Results (max last 5 lines):
INFO:root:command: make -f Makefile lint
ERROR:root:Make target returned non-zero.
  hooks/nova_cc_hooks.py:857:1: E302 expected 2 blank lines, found 1
  hooks/nova_cc_hooks.py:904:1: E302 expected 2 blank lines, found 1
  make: *** [lint] Error 1

Full lint test output: http://paste.ubuntu.com/9063889/
Build: http://10.98.191.181:8080/job/charm_lint_check/1116/

[uosci-testing-bot (uosci-testing-bot)]

UOSCI bot says:
charm_unit_test #950 trusty-nova-cloud-controller for brad-marshall mp241489
    UNIT FAIL: unit-test failed

UNIT Results (max last 5 lines):
  TOTAL 1071 391 63%
  Ran 96 tests in 9.558s
  FAILED (errors=2)
  maERROR:root:Make target returned non-zero.
ke: *** [unit_test] Error 1

Full unit test output: http://paste.ubuntu.com/9063906/
Build: http://10.98.191.181:8080/job/charm_unit_test/950/

[uosci-testing-bot (uosci-testing-bot)]

UOSCI bot says:
charm_amulet_test #458 trusty-nova-cloud-controller for brad-marshall mp241489
    AMULET FAIL: amulet-test failed

AMULET Results (max last 5 lines):
  juju-test.conductor DEBUG : Calling "juju destroy-environment -y osci-sv02"
  WARNING cannot delete security group "juju-osci-sv02-0". Used by another environment?
  juju-test INFO : Results: 1 passed, 2 failed, 0 errored
  ERROR subprocess encountered error code 2
  make: *** [test] Error 2

Full amulet test output: http://paste.ubuntu.com/9063966/
Build: http://10.98.191.181:8080/job/charm_amulet_test/458/

[uosci-testing-bot (uosci-testing-bot)]

UOSCI bot says:
charm_lint_check #1250 trusty-nova-cloud-controller for brad-marshall mp241489
    LINT FAIL: lint-test failed

LINT Results (max last 5 lines):
INFO:root:command: make -f Makefile lint
ERROR:root:Make target returned non-zero.
  hooks/nova_cc_hooks.py:857:1: E302 expected 2 blank lines, found 1
  hooks/nova_cc_hooks.py:904:1: E302 expected 2 blank lines, found 1
  make: *** [lint] Error 1

Full lint test output: http://paste.ubuntu.com/9281295/
Build: http://10.98.191.181:8080/job/charm_lint_check/1250/

[uosci-testing-bot (uosci-testing-bot)]

UOSCI bot says:
charm_unit_test #1084 trusty-nova-cloud-controller for brad-marshall mp241489
    UNIT FAIL: unit-test failed

UNIT Results (max last 5 lines):
  TOTAL 1071 391 63%
  Ran 96 tests in 10.716s
  FAILED (errors=2)
  mERROR:root:Make target returned non-zero.
ake: *** [unit_test] Error 1

Full unit test output: http://paste.ubuntu.com/9281305/
Build: http://10.98.191.181:8080/job/charm_unit_test/1084/

[uosci-testing-bot (uosci-testing-bot)]

UOSCI bot says:
charm_amulet_test #553 trusty-nova-cloud-controller for brad-marshall mp241489
    AMULET FAIL: amulet-test failed

AMULET Results (max last 5 lines):
  juju-test.conductor DEBUG : Calling "juju destroy-environment -y osci-sv04"
  WARNING cannot delete security group "juju-osci-sv04-0". Used by another environment?
  juju-test INFO : Results: 1 passed, 2 failed, 0 errored
  ERROR subprocess encountered error code 2
  make: *** [test] Error 2

Full amulet test output: http://paste.ubuntu.com/9281416/
Build: http://10.98.191.181:8080/job/charm_amulet_test/553/

[Liam Young (gnuoy)]

Thank for the mp. The new nrpe support is very gratefully received !

I've taken this branch and centralised the common code between this and the other nrpe branches and moved it to charm-helpers. To land it I created a new branch from this one which has now been merged into the 'next' charm. The 'next' charms will overwrite the stable ones in a couple of weeks.

review: Disapprove

=== modified file 'charm-helpers-hooks.yaml'
--- charm-helpers-hooks.yaml	2014-10-02 09:22:36 +0000
+++ charm-helpers-hooks.yaml	2014-11-18 01:21:59 +0000
@@ -10,3 +10,4 @@
     - payload.execd
     - contrib.network.ip
     - contrib.peerstorage
+    - contrib.charmsupport

=== modified file 'config.yaml'
--- config.yaml	2014-10-22 21:09:02 +0000
+++ config.yaml	2014-11-18 01:21:59 +0000
@@ -292,3 +292,14 @@
       order for this charm to function correctly, the privacy extension must be
       disabled and a non-temporary address must be configured/available on
       your network interface.
+  nagios_context:
+    default: "juju"
+    type: string
+    description: |
+      Used by the nrpe-external-master subordinate charm.
+      A string that will be prepended to instance name to set the host name
+      in nagios. So for instance the hostname would be something like:
+          juju-myservice-0
+      If you're running multiple environments with the same services in them
+      this allows you to differentiate between them.
+

=== added directory 'hooks/charmhelpers/contrib/charmsupport'
=== added file 'hooks/charmhelpers/contrib/charmsupport/__init__.py'
=== added file 'hooks/charmhelpers/contrib/charmsupport/nrpe.py'
--- hooks/charmhelpers/contrib/charmsupport/nrpe.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/contrib/charmsupport/nrpe.py	2014-11-18 01:21:59 +0000
@@ -0,0 +1,222 @@
+"""Compatibility with the nrpe-external-master charm"""
+# Copyright 2012 Canonical Ltd.
+#
+# Authors:
+#  Matthew Wedgwood <[e-mail]>
+
+import subprocess
+import pwd
+import grp
+import os
+import re
+import shlex
+import yaml
+
+from charmhelpers.core.hookenv import (
+    config,
+    local_unit,
+    log,
+    relation_ids,
+    relation_set,
+)
+
+from charmhelpers.core.host import service
+
+# This module adds compatibility with the nrpe-external-master and plain nrpe
+# subordinate charms. To use it in your charm:
+#
+# 1. Update metadata.yaml
+#
+#   provides:
+#     (...)
+#     nrpe-external-master:
+#       interface: nrpe-external-master
+#       scope: container
+#
+#   and/or
+#
+#   provides:
+#     (...)
+#     local-monitors:
+#       interface: local-monitors
+#       scope: container
+
+#
+# 2. Add the following to config.yaml
+#
+#    nagios_context:
+#      default: "juju"
+#      type: string
+#      description: |
+#        Used by the nrpe subordinate charms.
+#        A string that will be prepended to instance name to set the host name
+#        in nagios. So for instance the hostname would be something like:
+#            juju-myservice-0
+#        If you're running multiple environments with the same services in them
+#        this allows you to differentiate between them.
+#
+# 3. Add custom checks (Nagios plugins) to files/nrpe-external-master
+#
+# 4. Update your hooks.py with something like this:
+#
+#    from charmsupport.nrpe import NRPE
+#    (...)
+#    def update_nrpe_config():
+#        nrpe_compat = NRPE()
+#        nrpe_compat.add_check(
+#            shortname = "myservice",
+#            description = "Check MyService",
+#            check_cmd = "check_http -w 2 -c 10 http://localhost"
+#            )
+#        nrpe_compat.add_check(
+#            "myservice_other",
+#            "Check for widget failures",
+#            check_cmd = "/srv/myapp/scripts/widget_check"
+#            )
+#        nrpe_compat.write()
+#
+#    def config_changed():
+#        (...)
+#        update_nrpe_config()
+#
+#    def nrpe_external_master_relation_changed():
+#        update_nrpe_config()
+#
+#    def local_monitors_relation_changed():
+#        update_nrpe_config()
+#
+# 5. ln -s hooks.py nrpe-external-master-relation-changed
+#    ln -s hooks.py local-monitors-relation-changed
+
+
+class CheckException(Exception):
+    pass
+
+
+class Check(object):
+    shortname_re = '[A-Za-z0-9-_]+$'
+    service_template = ("""
+#---------------------------------------------------
+# This file is Juju managed
+#---------------------------------------------------
+define service {{
+    use                             active-service
+    host_name                       {nagios_hostname}
+    service_description             {nagios_hostname}[{shortname}] """
+                        """{description}
+    check_command                   check_nrpe!{command}
+    servicegroups                   {nagios_servicegroup}
+}}
+""")
+
+    def __init__(self, shortname, description, check_cmd):
+        super(Check, self).__init__()
+        # XXX: could be better to calculate this from the service name
+        if not re.match(self.shortname_re, shortname):
+            raise CheckException("shortname must match {}".format(
+                Check.shortname_re))
+        self.shortname = shortname
+        self.command = "check_{}".format(shortname)
+        # Note: a set of invalid characters is defined by the
+        # Nagios server config
+        # The default is: illegal_object_name_chars=`~!$%^&*"|'<>?,()=
+        self.description = description
+        self.check_cmd = self._locate_cmd(check_cmd)
+
+    def _locate_cmd(self, check_cmd):
+        search_path = (
+            '/',
+            os.path.join(os.environ['CHARM_DIR'],
+                         'files/nrpe-external-master'),
+            '/usr/lib/nagios/plugins',
+            '/usr/local/lib/nagios/plugins',
+        )
+        parts = shlex.split(check_cmd)
+        for path in search_path:
+            if os.path.exists(os.path.join(path, parts[0])):
+                command = os.path.join(path, parts[0])
+                if len(parts) > 1:
+                    command += " " + " ".join(parts[1:])
+                return command
+        log('Check command not found: {}'.format(parts[0]))
+        return ''
+
+    def write(self, nagios_context, hostname):
+        nrpe_check_file = '/etc/nagios/nrpe.d/{}.cfg'.format(
+            self.command)
+        with open(nrpe_check_file, 'w') as nrpe_check_config:
+            nrpe_check_config.write("# check {}\n".format(self.shortname))
+            nrpe_check_config.write("command[{}]={}\n".format(
+                self.command, self.check_cmd))
+
+        if not os.path.exists(NRPE.nagios_exportdir):
+            log('Not writing service config as {} is not accessible'.format(
+                NRPE.nagios_exportdir))
+        else:
+            self.write_service_config(nagios_context, hostname)
+
+    def write_service_config(self, nagios_context, hostname):
+        for f in os.listdir(NRPE.nagios_exportdir):
+            if re.search('.*{}.cfg'.format(self.command), f):
+                os.remove(os.path.join(NRPE.nagios_exportdir, f))
+
+        templ_vars = {
+            'nagios_hostname': hostname,
+            'nagios_servicegroup': nagios_context,
+            'description': self.description,
+            'shortname': self.shortname,
+            'command': self.command,
+        }
+        nrpe_service_text = Check.service_template.format(**templ_vars)
+        nrpe_service_file = '{}/service__{}_{}.cfg'.format(
+            NRPE.nagios_exportdir, hostname, self.command)
+        with open(nrpe_service_file, 'w') as nrpe_service_config:
+            nrpe_service_config.write(str(nrpe_service_text))
+
+    def run(self):
+        subprocess.call(self.check_cmd)
+
+
+class NRPE(object):
+    nagios_logdir = '/var/log/nagios'
+    nagios_exportdir = '/var/lib/nagios/export'
+    nrpe_confdir = '/etc/nagios/nrpe.d'
+
+    def __init__(self, hostname=None):
+        super(NRPE, self).__init__()
+        self.config = config()
+        self.nagios_context = self.config['nagios_context']
+        self.unit_name = local_unit().replace('/', '-')
+        if hostname:
+            self.hostname = hostname
+        else:
+            self.hostname = "{}-{}".format(self.nagios_context, self.unit_name)
+        self.checks = []
+
+    def add_check(self, *args, **kwargs):
+        self.checks.append(Check(*args, **kwargs))
+
+    def write(self):
+        try:
+            nagios_uid = pwd.getpwnam('nagios').pw_uid
+            nagios_gid = grp.getgrnam('nagios').gr_gid
+        except:
+            log("Nagios user not set up, nrpe checks not updated")
+            return
+
+        if not os.path.exists(NRPE.nagios_logdir):
+            os.mkdir(NRPE.nagios_logdir)
+            os.chown(NRPE.nagios_logdir, nagios_uid, nagios_gid)
+
+        nrpe_monitors = {}
+        monitors = {"monitors": {"remote": {"nrpe": nrpe_monitors}}}
+        for nrpecheck in self.checks:
+            nrpecheck.write(self.nagios_context, self.hostname)
+            nrpe_monitors[nrpecheck.shortname] = {
+                "command": nrpecheck.command,
+            }
+
+        service('restart', 'nagios-nrpe-server')
+
+        for rid in relation_ids("local-monitors"):
+            relation_set(relation_id=rid, monitors=yaml.dump(monitors))

=== added file 'hooks/charmhelpers/contrib/charmsupport/volumes.py'
--- hooks/charmhelpers/contrib/charmsupport/volumes.py	1970-01-01 00:00:00 +0000
+++ hooks/charmhelpers/contrib/charmsupport/volumes.py	2014-11-18 01:21:59 +0000
@@ -0,0 +1,156 @@
+'''
+Functions for managing volumes in juju units. One volume is supported per unit.
+Subordinates may have their own storage, provided it is on its own partition.
+
+Configuration stanzas:
+  volume-ephemeral:
+    type: boolean
+    default: true
+    description: >
+      If false, a volume is mounted as sepecified in "volume-map"
+      If true, ephemeral storage will be used, meaning that log data
+         will only exist as long as the machine. YOU HAVE BEEN WARNED.
+  volume-map:
+    type: string
+    default: {}
+    description: >
+      YAML map of units to device names, e.g:
+        "{ rsyslog/0: /dev/vdb, rsyslog/1: /dev/vdb }"
+      Service units will raise a configure-error if volume-ephemeral
+      is 'true' and no volume-map value is set. Use 'juju set' to set a
+      value and 'juju resolved' to complete configuration.
+
+Usage:
+    from charmsupport.volumes import configure_volume, VolumeConfigurationError
+    from charmsupport.hookenv import log, ERROR
+    def post_mount_hook():
+        stop_service('myservice')
+    def post_mount_hook():
+        start_service('myservice')
+
+    if __name__ == '__main__':
+        try:
+            configure_volume(before_change=pre_mount_hook,
+                             after_change=post_mount_hook)
+        except VolumeConfigurationError:
+            log('Storage could not be configured', ERROR)
+'''
+
+# XXX: Known limitations
+# - fstab is neither consulted nor updated
+
+import os
+from charmhelpers.core import hookenv
+from charmhelpers.core import host
+import yaml
+
+
+MOUNT_BASE = '/srv/juju/volumes'
+
+
+class VolumeConfigurationError(Exception):
+    '''Volume configuration data is missing or invalid'''
+    pass
+
+
+def get_config():
+    '''Gather and sanity-check volume configuration data'''
+    volume_config = {}
+    config = hookenv.config()
+
+    errors = False
+
+    if config.get('volume-ephemeral') in (True, 'True', 'true', 'Yes', 'yes'):
+        volume_config['ephemeral'] = True
+    else:
+        volume_config['ephemeral'] = False
+
+    try:
+        volume_map = yaml.safe_load(config.get('volume-map', '{}'))
+    except yaml.YAMLError as e:
+        hookenv.log("Error parsing YAML volume-map: {}".format(e),
+                    hookenv.ERROR)
+        errors = True
+    if volume_map is None:
+        # probably an empty string
+        volume_map = {}
+    elif not isinstance(volume_map, dict):
+        hookenv.log("Volume-map should be a dictionary, not {}".format(
+            type(volume_map)))
+        errors = True
+
+    volume_config['device'] = volume_map.get(os.environ['JUJU_UNIT_NAME'])
+    if volume_config['device'] and volume_config['ephemeral']:
+        # asked for ephemeral storage but also defined a volume ID
+        hookenv.log('A volume is defined for this unit, but ephemeral '
+                    'storage was requested', hookenv.ERROR)
+        errors = True
+    elif not volume_config['device'] and not volume_config['ephemeral']:
+        # asked for permanent storage but did not define volume ID
+        hookenv.log('Ephemeral storage was requested, but there is no volume '
+                    'defined for this unit.', hookenv.ERROR)
+        errors = True
+
+    unit_mount_name = hookenv.local_unit().replace('/', '-')
+    volume_config['mountpoint'] = os.path.join(MOUNT_BASE, unit_mount_name)
+
+    if errors:
+        return None
+    return volume_config
+
+
+def mount_volume(config):
+    if os.path.exists(config['mountpoint']):
+        if not os.path.isdir(config['mountpoint']):
+            hookenv.log('Not a directory: {}'.format(config['mountpoint']))
+            raise VolumeConfigurationError()
+    else:
+        host.mkdir(config['mountpoint'])
+    if os.path.ismount(config['mountpoint']):
+        unmount_volume(config)
+    if not host.mount(config['device'], config['mountpoint'], persist=True):
+        raise VolumeConfigurationError()
+
+
+def unmount_volume(config):
+    if os.path.ismount(config['mountpoint']):
+        if not host.umount(config['mountpoint'], persist=True):
+            raise VolumeConfigurationError()
+
+
+def managed_mounts():
+    '''List of all mounted managed volumes'''
+    return filter(lambda mount: mount[0].startswith(MOUNT_BASE), host.mounts())
+
+
+def configure_volume(before_change=lambda: None, after_change=lambda: None):
+    '''Set up storage (or don't) according to the charm's volume configuration.
+       Returns the mount point or "ephemeral". before_change and after_change
+       are optional functions to be called if the volume configuration changes.
+    '''
+
+    config = get_config()
+    if not config:
+        hookenv.log('Failed to read volume configuration', hookenv.CRITICAL)
+        raise VolumeConfigurationError()
+
+    if config['ephemeral']:
+        if os.path.ismount(config['mountpoint']):
+            before_change()
+            unmount_volume(config)
+            after_change()
+        return 'ephemeral'
+    else:
+        # persistent storage
+        if os.path.ismount(config['mountpoint']):
+            mounts = dict(managed_mounts())
+            if mounts.get(config['mountpoint']) != config['device']:
+                before_change()
+                unmount_volume(config)
+                mount_volume(config)
+                after_change()
+        else:
+            before_change()
+            mount_volume(config)
+            after_change()
+        return config['mountpoint']

=== modified file 'hooks/nova_cc_hooks.py'
--- hooks/nova_cc_hooks.py	2014-10-23 07:32:45 +0000
+++ hooks/nova_cc_hooks.py	2014-11-18 01:21:59 +0000
@@ -20,6 +20,7 @@
     relation_get,
     relation_ids,
     relation_set,
+    relations_of_type,
     related_units,
     open_port,
     unit_get,
@@ -116,6 +117,8 @@
 
 from charmhelpers.contrib.openstack.context import ADDRESS_TYPES
 
+from charmhelpers.contrib.charmsupport.nrpe import NRPE
+
 hooks = Hooks()
 CONFIGS = register_configs()
 
@@ -131,8 +134,9 @@
     if os.path.isdir(_files):
         for f in os.listdir(_files):
             f = os.path.join(_files, f)
-            log('Installing %s to /usr/bin' % f)
-            shutil.copy2(f, '/usr/bin')
+            if os.path.isfile(f):
+                log('Installing %s to /usr/bin' % f)
+                shutil.copy2(f, '/usr/bin')
     [open_port(port) for port in determine_ports()]
     log('Disabling services into db relation joined')
     disable_services()
@@ -166,6 +170,7 @@
     for r_id in relation_ids('identity-service'):
         identity_joined(rid=r_id)
     [cluster_joined(rid) for rid in relation_ids('cluster')]
+    update_nrpe_config()
 
 
 @hooks.hook('amqp-relation-joined')
@@ -775,6 +780,7 @@
     for r_id in relation_ids('cloud-compute'):
         for unit in related_units(r_id):
             compute_changed(r_id, unit)
+    update_nrpe_config()
 
 
 # remote_restart is defaulted to true as nova-cells may have started the
@@ -848,6 +854,52 @@
     for rid in relation_ids('quantum-network-service'):
         quantum_joined(rid=rid)
 
[e-mail]('nrpe-external-master-relation-joined',
+            'nrpe-external-master-relation-changed')
+def update_nrpe_config():
+    # Find out if nrpe set nagios_hostname
+    hostname = None
+    host_context = None
+    for rel in relations_of_type('nrpe-external-master'):
+        if 'nagios_hostname' in rel:
+            hostname = rel['nagios_hostname']
+            host_context = rel['nagios_host_context']
+            break
+    nrpe = NRPE(hostname=hostname)
+    apt_install('python-dbus')
+
+    if host_context:
+        current_unit = "%s:%s" % (host_context, local_unit())
+    else:
+        current_unit = local_unit()
+
+    services_to_monitor = services()
+    for service in services_to_monitor:
+        upstart_init = '/etc/init/%s.conf' % service
+        sysv_init = '/etc/init.d/%s' % service
+
+        if os.path.exists(upstart_init):
+            nrpe.add_check(
+                shortname=service,
+                description='process check {%s}' % current_unit,
+                check_cmd='check_upstart_job %s' % service,
+                )
+        elif os.path.exists(sysv_init):
+            cronpath = '/etc/cron.d/nagios-service-check-%s' % service
+            cron_template = '*/5 * * * * root \
+/usr/local/lib/nagios/plugins/check_exit_status.pl -s /etc/init.d/%s \
+status > /var/lib/nagios/service-check-%s.txt\n' % (service, service)
+            f = open(cronpath, 'w')
+            f.write(cron_template)
+            f.close()
+            nrpe.add_check(
+                shortname=service,
+                description='process check {%s}' % current_unit,
+                check_cmd='check_status_file.py -f \
+/var/lib/nagios/service-check-%s.txt' % service,
+                )
+
+    nrpe.write()
 
 def main():
     try:

=== added symlink 'hooks/nrpe-external-master-relation-changed'
=== target is u'nova_cc_hooks.py'
=== added symlink 'hooks/nrpe-external-master-relation-joined'
=== target is u'nova_cc_hooks.py'
=== modified file 'metadata.yaml'
--- metadata.yaml	2014-07-11 09:14:57 +0000
+++ metadata.yaml	2014-11-18 01:21:59 +0000
@@ -7,6 +7,9 @@
 categories:
   - openstack
 provides:
+  nrpe-external-master:
+    interface: nrpe-external-master
+    scope: container
   cloud-controller:
     interface: nova
 requires: