glance/doc/source/controllingservers.rst

Controlling Glance Servers

This section describes the ways to start, stop, and reload Glance's server programs.

Starting a server

There are two ways to start a Glance server (either the API server or the reference implementation registry server that ships with Glance):

• Manually calling the server program
• Using the glance-control server daemon wrapper program

Manually starting the server

The first is by directly calling the server program, passing in command-line options and a single argument for the paste.deploy configuration file to use when configuring the server application.

Note

Glance ships with an etc/ directory that contains sample paste.deploy configuration files that you can copy to a standard configuation directory and adapt for your own uses.

If you do not specifiy a configuration file on the command line, Glance will do its best to locate a glance.conf configuration file in one of the following directories, stopping at the first config file it finds:

• .
• ~/.glance
• ~/
• /etc/glance/
• /etc

If no configuration file is found, you will see any error, like so:

$> glance-api
ERROR: Unable to locate any configuration file. Cannot load application glance-api

Here is an example showing how you can manually start the glance-api server in a shell.:

$> sudo glance-api etc/glance.conf.sample --debug
2011-02-09 14:58:29    DEBUG [glance-api] ********************************************************************************
2011-02-09 14:58:29    DEBUG [glance-api] Configuration options gathered from config file:
2011-02-09 14:58:29    DEBUG [glance-api] /home/jpipes/repos/glance/trunk/etc/glance.conf.sample
2011-02-09 14:58:29    DEBUG [glance-api] ================================================
2011-02-09 14:58:29    DEBUG [glance-api] bind_host                      0.0.0.0
2011-02-09 14:58:29    DEBUG [glance-api] bind_port                      9292
2011-02-09 14:58:29    DEBUG [glance-api] debug                          True
2011-02-09 14:58:29    DEBUG [glance-api] default_store                  file
2011-02-09 14:58:29    DEBUG [glance-api] filesystem_store_datadir       /var/lib/glance/images/
2011-02-09 14:58:29    DEBUG [glance-api] registry_host                  0.0.0.0
2011-02-09 14:58:29    DEBUG [glance-api] registry_port                  9191
2011-02-09 14:58:29    DEBUG [glance-api] verbose                        False
2011-02-09 14:58:29    DEBUG [glance-api] ********************************************************************************
2011-02-09 14:58:29    DEBUG [routes.middleware] Initialized with method overriding = True, and path info altering = True
(16333) wsgi starting up on http://0.0.0.0:9292/

Simply supply the configuration file as the first argument (etc/glance.conf.sample in the above example) and then any common options you want to use (--debug was used above to show some of the debugging output that the server shows when starting up. Call the server program with --help to see all available options you can specify on the command line.)

For more information on configuring the server via the paste.deploy configuration files, see the section entitled Configuring Glance servers <configuring>

Note that the server does not daemonize itself when run manually from the terminal. You can force the server to daemonize using the standard shell backgrounding indicator, &. However, for most use cases, we recommend using the glance-control server daemon wrapper for daemonizing. See below for more details on daemonization with glance-control.

Using the glance-control program to start the server

The second way to start up a Glance server is to use the glance-control program. glance-control is a wrapper script that allows the user to start, stop, restart, and reload the other Glance server programs in a fashion that is more conducive to automation and scripting.

Servers started via the glance-control program are always daemonized, meaning that the server program process runs in the background.

To start a Glance server with glance-control, simply call glance-control with a server and the word "start", followed by any command-line options you wish to provide. Start the server with glance-control in the following way:

$> sudo glance-control <SERVER> start [CONFPATH]

Note

You must use the sudo program to run glance-control currently, as the pid files for the server programs are written to /var/run/glance/

Here is an example that shows how to start the glance-registry server with the glance-control wrapper script. :

$> sudo glance-control registry start etc/glance.conf.sample
Starting glance-registry with /home/jpipes/repos/glance/trunk/etc/glance.conf.sample

The same paste.deploy configuration files are used by glance-control to start the Glance server programs, and you can specify (as the example above shows) a configuration file when starting the server.

Note

To start all the Glance servers (currently the glance-api and glance-registry programs) at once, you can specify "all" for the <SERVER>

Stopping a server

If you started a Glance server manually and did not use the & backgrounding function, simply send a terminate signal to the server process by typing Ctrl-C

If you started the Glance server using the glance-control program, you can use the glance-control program to stop it. Simply do the following:

$> sudo glance-control <SERVER> stop

as this example shows:

$> sudo glance-control registry stop
Stopping glance-registry  pid: 17602  signal: 15

Restarting a server

You can restart a server with the glance-control program, as demonstrated here:

$> sudo glance-control registry restart etc/glance.conf.sample
Stopping glance-registry  pid: 17611  signal: 15
Starting glance-registry with /home/jpipes/repos/glance/trunk/etc/glance.conf.sample