xenserver/etc_xapi.d_plugins_openvswitch-cfg-update

   1 #!/usr/bin/env python
   2 #
   3 # xapi plugin script to update the cache of configuration items in the
   4 # ovs-vswitchd configuration that are managed in the xapi database when
   5 # integrated with Citrix management tools.
   6
   7 # Copyright (C) 2009, 2010, 2011 Nicira Networks, Inc.
   8 #
   9 # Licensed under the Apache License, Version 2.0 (the "License");
  10 # you may not use this file except in compliance with the License.
  11 # You may obtain a copy of the License at:
  12 #
  13 #     http://www.apache.org/licenses/LICENSE-2.0
  14 #
  15 # Unless required by applicable law or agreed to in writing, software
  16 # distributed under the License is distributed on an "AS IS" BASIS,
  17 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  18 # See the License for the specific language governing permissions and
  19 # limitations under the License.
  20
  21 # TBD: - error handling needs to be improved.  Currently this can leave
  22 # TBD:   the system in a bad state if anything goes wrong.
  23
  24 import XenAPIPlugin
  25 import XenAPI
  26 import os
  27 import subprocess
  28 import syslog
  29
  30 vsctl="/usr/bin/ovs-vsctl"
  31 cacert_filename="/etc/openvswitch/vswitchd.cacert"
  32
  33 # Delete the CA certificate, so that we go back to boot-strapping mode
  34 def delete_cacert():
  35     try:
  36         os.remove(cacert_filename)
  37     except OSError:
  38         # Ignore error if file doesn't exist
  39         pass
  40
  41 def update(session, args):
  42     # Refresh bridge network UUIDs in case this host joined or left a pool.
  43     script = "/opt/xensource/libexec/interface-reconfigure"
  44     try:
  45         retval = subprocess.call([script, "rewrite"])
  46         if retval != 0:
  47             syslog.syslog("%s exited with status %d" % (script, retval))
  48     except OSError, e:
  49         syslog.syslog("%s: failed to execute (%s)" % (script, e.strerror))
  50
  51     pools = session.xenapi.pool.get_all()
  52     # We assume there is only ever one pool...
  53     if len(pools) == 0:
  54         raise XenAPIPlugin.Failure("NO_POOL_FOR_HOST", [])
  55     if len(pools) > 1:
  56         raise XenAPIPlugin.Failure("MORE_THAN_ONE_POOL_FOR_HOST", [])
  57     pool = session.xenapi.pool.get_record(pools[0])
  58     controller = pool.get("vswitch_controller", "")
  59     ret_str = ""
  60     currentController = vswitchCurrentController()
  61     if controller == "" and currentController != "":
  62         delete_cacert()
  63         try:
  64             emergency_reset(session, None)
  65         except:
  66             pass
  67         removeControllerCfg()
  68         ret_str += "Successfully removed controller config.  "
  69     elif controller != currentController:
  70         delete_cacert()
  71         try:
  72             emergency_reset(session, None)
  73         except:
  74             pass
  75         setControllerCfg(controller)
  76         ret_str += "Successfully set controller to %s.  " % controller
  77
  78     try:
  79         pool_fail_mode = pool["other_config"]["vswitch-controller-fail-mode"]
  80     except KeyError, e:
  81         pool_fail_mode = None
  82
  83     bton = {}
  84
  85     for n in session.xenapi.network.get_all():
  86         rec = session.xenapi.network.get_record(n)
  87         try:
  88             bton[rec['bridge']] = rec
  89         except KeyError:
  90             pass
  91
  92     dib_changed = False
  93     fail_mode_changed = False
  94     for bridge in vswitchCfgQuery(['list-br']).split():
  95         network = bton[bridge]
  96         bridge = vswitchCfgQuery(['br-to-parent', bridge])
  97
  98         xapi_dib = network['other_config'].get('vswitch-disable-in-band')
  99         if not xapi_dib:
 100             xapi_dib = ''
 101
 102         ovs_dib = vswitchCfgQuery(['--', '--if-exists', 'get', 'Bridge',
 103                                    bridge,
 104                                    'other_config:disable-in-band']).strip('"')
 105
 106         # Do nothing if setting is invalid, and warn the user.
 107         if xapi_dib not in ['true', 'false', '']:
 108             ret_str += '"' + xapi_dib + '"' + \
 109                 ' is an invalid value for vswitch-disable-in-band on ' + \
 110                 bridge + '  '
 111
 112         # Change bridge disable-in-band option if XAPI and OVS states differ.
 113         elif xapi_dib != ovs_dib:
 114             # 'true' or 'false'
 115             if xapi_dib:
 116                 vswitchCfgMod(['--', 'set', 'Bridge', bridge,
 117                                'other_config:disable-in-band=' + xapi_dib])
 118             # '' or None
 119             else:
 120                 vswitchCfgMod(['--', 'remove', 'Bridge', bridge,
 121                                'other_config', 'disable-in-band'])
 122             dib_changed = True
 123
 124         # Change bridge fail_mode if XAPI state differs from OVS state.
 125         bridge_fail_mode = vswitchCfgQuery(["get", "Bridge",
 126             bridge, "fail_mode"]).strip('[]"')
 127
 128         try:
 129             fail_mode = bton[bridge]["other_config"]["vswitch-controller-fail-mode"]
 130         except KeyError, e:
 131             fail_mode = None
 132
 133         if fail_mode not in ['secure', 'standalone']:
 134             fail_mode = pool_fail_mode
 135
 136         if fail_mode != 'secure':
 137             fail_mode = 'standalone'
 138
 139         if bridge_fail_mode != fail_mode:
 140             vswitchCfgMod(['--', 'set', 'Bridge', bridge,
 141                 "fail_mode=%s" % fail_mode])
 142             fail_mode_changed = True
 143
 144     if dib_changed:
 145         ret_str += "Updated in-band management.  "
 146     if fail_mode_changed:
 147         ret_str += "Updated fail_mode.  "
 148
 149     if ret_str != '':
 150         return ret_str
 151     else:
 152         return "No change to configuration"
 153
 154 def vswitchCurrentController():
 155     controller = vswitchCfgQuery(["get-manager"])
 156     if controller == "":
 157         return controller
 158     if len(controller) < 4 or controller[0:4] != "ssl:":
 159         return controller
 160     else:
 161         return controller.split(':')[1]
 162
 163 def removeControllerCfg():
 164     vswitchCfgMod(["--", "del-manager",
 165                    "--", "del-ssl"])
 166
 167 def setControllerCfg(controller):
 168     # /etc/xensource/xapi-ssl.pem is mentioned twice below because it
 169     # contains both the private key and the certificate.
 170     vswitchCfgMod(["--", "del-manager",
 171                    "--", "del-ssl",
 172                    "--", "--bootstrap", "set-ssl",
 173                    "/etc/xensource/xapi-ssl.pem",
 174                    "/etc/xensource/xapi-ssl.pem",
 175                    cacert_filename,
 176                    "--", "set-manager", 'ssl:' + controller + ':6632'])
 177
 178 def vswitchCfgQuery(action_args):
 179     cmd = [vsctl, "--timeout=5", "-vANY:console:emer"] + action_args
 180     output = subprocess.Popen(cmd, stdout=subprocess.PIPE).communicate()
 181     if len(output) == 0 or output[0] == None:
 182         output = ""
 183     else:
 184         output = output[0].strip()
 185     return output
 186
 187 def vswitchCfgMod(action_args):
 188     cmd = [vsctl, "--timeout=5", "-vANY:console:emer"] + action_args
 189     exitcode = subprocess.call(cmd)
 190     if exitcode != 0:
 191         raise XenAPIPlugin.Failure("VSWITCH_CONFIG_MOD_FAILURE",
 192                                    [ str(exitcode) , str(action_args) ])
 193
 194 def emergency_reset(session, args):
 195     cmd = [vsctl, "--timeout=5", "emer-reset"]
 196     exitcode = subprocess.call(cmd)
 197     if exitcode != 0:
 198         raise XenAPIPlugin.Failure("VSWITCH_EMER_RESET_FAILURE",
 199                                    [ str(exitcode) ])
 200
 201     return "Successfully reset configuration"
 202
 203 if __name__ == "__main__":
 204     XenAPIPlugin.dispatch({"update": update,
 205                            "emergency_reset": emergency_reset})