Installing the API Behind mod_wsgi

Ceilometer comes with a few example files for configuring the API service to run behind Apache with mod_wsgi.

app.wsgi

The file ceilometer/api/app.wsgi sets up the V2 API WSGI application. The file is installed with the rest of the ceilometer application code, and should not need to be modified.

etc/apache2/ceilometer

The etc/apache2/ceilometer file contains example settings that work with a copy of ceilometer installed via devstack.

# Copyright (c) 2013 New Dream Network, LLC (DreamHost)
#
# Author: Doug Hellmann <[email protected]>
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.

# This is an example Apache2 configuration file for using the
# ceilometer API through mod_wsgi.  This version assumes you are
# running devstack to configure the software.

<VirtualHost *>
    WSGIDaemonProcess ceilometer user=vagrant group=vagrant threads=5
    WSGIScriptAlias / /opt/stack/ceilometer/ceilometer/api/app.wsgi

    SetEnv APACHE_RUN_USER vagrant
    SetEnv APACHE_RUN_GROUP vagrant
    WSGIProcessGroup ceilometer

    ErrorLog /var/log/apache2/ceilometer_error.log
    LogLevel warn
    CustomLog /var/log/apache2/ceilometer_access.log combined

</VirtualHost>

1. Copy or symlink the file to /etc/apache2/sites-avilable.
2. Modify the VirtualHost directive, setting a hostname or IP for the service. The default settings assume that the ceilometer API is the only service running on the local Apache instance, which conflicts with Horizon’s default configuration.
3. Modify the WSGIDaemonProcess directive to set the

user and group values to a user available on your server.

4. Modify the APACHE_RUN_USER and APACHE_RUN_GROUP values to the name of a user and group available on your server.

5. Enable the ceilometer site.

   $ a2ensite ceilometer
   $ service apache2 reload