Running Keystone in HTTPD

mod_proxy_uwsgi

The recommended keystone deployment is to have a real web server such as Apache HTTPD or nginx handle the HTTP connections and proxy requests to an independent keystone server (or servers) running under a wsgi container such as uwsgi or gunicorn. The typical deployment will have several applications proxied by the web server (for example horizon on /dashboard and keystone on /identity, /identity_admin, port :5000, and :35357). Proxying allows the applications to be shut down and restarted independently, and a problem in one application isn’t going to affect the web server or other applications. The servers can easily be run in their own virtualenvs.

The httpd/ directory contains sample files for configuring HTTPD to proxy requests to keystone servers running under uwsgi.

Copy the httpd/uwsgi-keystone.conf sample configuration file to the appropriate location for your Apache server, on Debian/Ubuntu systems it is:

/etc/apache2/sites-available/uwsgi-keystone.conf

On Red Hat based systems it is:

/etc/httpd/conf.d/uwsgi-keystone.conf

Update the file to match your system configuration. Enable TLS by supplying the correct certificates.

Enable mod_proxy_uwsgi.

  • On Ubuntu the required package is libapache2-mod-proxy-uwsgi; enable using sudo a2enmod proxy
  • On Fedora the required package is mod_proxy_uwsgi; enable by creating a file /etc/httpd/conf.modules.d/11-proxy_uwsgi.conf containing LoadModule proxy_uwsgi_module modules/mod_proxy_uwsgi.so

Enable the site by creating a symlink from the file in sites-available to sites-enabled, for example, on Debian/Ubuntu systems (not required on Red Hat based systems):

ln -s /etc/apache2/sites-available/uwsgi-keystone.conf /etc/apache2/sites-enabled/

Start or restart HTTPD to pick up the new configuration.

Now configure and start the uwsgi services. Copy the httpd/keystone-uwsgi-admin.ini and httpd/keystone-uwsgi-public.ini files to /etc/keystone. Update the files to match your system configuration (for example, you’ll want to set the number of threads for the public and admin servers).

Start up the keystone servers using uwsgi:

$ sudo pip install uwsgi
$ uwsgi /etc/keystone/keystone-uwsgi-admin.ini
$ uwsgi /etc/keystone/keystone-uwsgi-public.ini

mod_wsgi

Warning

Running Keystone under HTTPD in this configuration does not support the use of Transfer-Encoding: chunked. This is due to a limitation with the WSGI spec and the implementation used by mod_wsgi. It is recommended that all clients assume Keystone will not support Transfer-Encoding: chunked.

Copy the httpd/wsgi-keystone.conf sample configuration file to the appropriate location for your Apache server, on Debian/Ubuntu systems it is:

/etc/apache2/sites-available/wsgi-keystone.conf

On Red Hat based systems it is:

/etc/httpd/conf.d/wsgi-keystone.conf

Update the file to match your system configuration. Note the following:

  • Make sure the correct log directory is used. Some distributions put httpd server logs in the apache2 directory and some in the httpd directory.
  • Enable TLS by supplying the correct certificates.

Keystone’s primary configuration file (etc/keystone.conf) and the PasteDeploy configuration file (etc/keystone-paste.ini) must be readable to HTTPD in one of the default locations described in Configuring Keystone.

Enable the site by creating a symlink from the file in sites-available to sites-enabled, for example, on Debian/Ubuntu systems (not required on Red Hat based systems):

ln -s /etc/apache2/sites-available/wsgi-keystone.conf /etc/apache2/sites-enabled/

Restart Apache to have it start serving keystone.

Access Control

If you are running with Linux kernel security module enabled (for example SELinux or AppArmor) make sure that the file has the appropriate context to access the linked file.

Keystone Configuration

Make sure that when using a token format that requires persistence, you use a token persistence driver that can be shared between processes. The SQL and memcached token persistence drivers provided with keystone can be shared between processes.

Warning

The KVS (kvs) token persistence driver cannot be shared between processes so must not be used when running keystone under HTTPD (the tokens will not be shared between the processes of the server and validation will fail).

For SQL, in /etc/keystone/keystone.conf set:

[token]
driver = sql

For memcached, in /etc/keystone/keystone.conf set:

[token]
driver = memcache

All servers that are storing tokens need a shared backend. This means that either all servers use the same database server or use a common memcached pool.