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 registry server):
- Manually calling the server program
- Using the
glance-controlserver daemon wrapper program
We recommend using the second method.
Manually starting the server¶
The first is by directly calling the server program, passing in command-line
options and a single argument for a 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 configuration directory and
adapt for your own uses. Specifically, bind_host must be set properly.
If you do not specify a configuration file on the command line, Glance will do its best to locate a configuration file in one of the following directories, stopping at the first config file it finds:
$CWD~/.glance~//etc/glance/etc
The filename that is searched for depends on the server application name. So,
if you are starting up the API server, glance-api.conf is searched for,
otherwise glance-registry.conf.
If no configuration file is found, you will see an error, like:
$> 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 and glance-registry in a shell.:
$ sudo glance-api --config-file glance-api.conf --debug &
jsuh@mc-ats1:~$ 2011-04-13 14:50:12 DEBUG [glance-api] ********************************************************************************
2011-04-13 14:50:12 DEBUG [glance-api] Configuration options gathered from config file:
2011-04-13 14:50:12 DEBUG [glance-api] /home/jsuh/glance-api.conf
2011-04-13 14:50:12 DEBUG [glance-api] ================================================
2011-04-13 14:50:12 DEBUG [glance-api] bind_host 65.114.169.29
2011-04-13 14:50:12 DEBUG [glance-api] bind_port 9292
2011-04-13 14:50:12 DEBUG [glance-api] debug True
2011-04-13 14:50:12 DEBUG [glance-api] default_store file
2011-04-13 14:50:12 DEBUG [glance-api] filesystem_store_datadir /home/jsuh/images/
2011-04-13 14:50:12 DEBUG [glance-api] registry_host 65.114.169.29
2011-04-13 14:50:12 DEBUG [glance-api] registry_port 9191
2011-04-13 14:50:12 DEBUG [glance-api] ********************************************************************************
2011-04-13 14:50:12 DEBUG [routes.middleware] Initialized with method overriding = True, and path info altering = True
2011-04-13 14:50:12 DEBUG [eventlet.wsgi.server] (21354) wsgi starting up on http://65.114.169.29:9292/
$ sudo glance-registry --config-file glance-registry.conf &
jsuh@mc-ats1:~$ 2011-04-13 14:51:16 INFO [sqlalchemy.engine.base.Engine.0x...feac] PRAGMA table_info("images")
2011-04-13 14:51:16 INFO [sqlalchemy.engine.base.Engine.0x...feac] ()
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Col ('cid', 'name', 'type', 'notnull', 'dflt_value', 'pk')
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (0, u'created_at', u'DATETIME', 1, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (1, u'updated_at', u'DATETIME', 0, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (2, u'deleted_at', u'DATETIME', 0, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (3, u'deleted', u'BOOLEAN', 1, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (4, u'id', u'INTEGER', 1, None, 1)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (5, u'name', u'VARCHAR(255)', 0, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (6, u'disk_format', u'VARCHAR(20)', 0, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (7, u'container_format', u'VARCHAR(20)', 0, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (8, u'size', u'INTEGER', 0, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (9, u'status', u'VARCHAR(30)', 1, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (10, u'is_public', u'BOOLEAN', 1, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (11, u'location', u'TEXT', 0, None, 0)
2011-04-13 14:51:16 INFO [sqlalchemy.engine.base.Engine.0x...feac] PRAGMA table_info("image_properties")
2011-04-13 14:51:16 INFO [sqlalchemy.engine.base.Engine.0x...feac] ()
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Col ('cid', 'name', 'type', 'notnull', 'dflt_value', 'pk')
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (0, u'created_at', u'DATETIME', 1, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (1, u'updated_at', u'DATETIME', 0, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (2, u'deleted_at', u'DATETIME', 0, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (3, u'deleted', u'BOOLEAN', 1, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (4, u'id', u'INTEGER', 1, None, 1)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (5, u'image_id', u'INTEGER', 1, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (6, u'key', u'VARCHAR(255)', 1, None, 0)
2011-04-13 14:51:16 DEBUG [sqlalchemy.engine.base.Engine.0x...feac] Row (7, u'value', u'TEXT', 0, None, 0)
$ ps aux | grep glance
root 20009 0.7 0.1 12744 9148 pts/1 S 12:47 0:00 /usr/bin/python /usr/bin/glance-api glance-api.conf --debug
root 20012 2.0 0.1 25188 13356 pts/1 S 12:47 0:00 /usr/bin/python /usr/bin/glance-registry glance-registry.conf
jsuh 20017 0.0 0.0 3368 744 pts/1 S+ 12:47 0:00 grep glance
Simply supply the configuration file as the parameter to the --config-file option
(the etc/glance-api.conf and etc/glance-registry.conf sample configuration
files were used in the above example) and then any other 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
Note that the server daemonizes itself by using the standard
shell backgrounding indicator, &, in the previous example. 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 [OPTIONS] <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 api start glance-api.conf
Starting glance-api with /home/jsuh/glance.conf
$ sudo glance-control registry start glance-registry.conf
Starting glance-registry with /home/jsuh/glance.conf
$ ps aux | grep glance
root 20038 4.0 0.1 12728 9116 ? Ss 12:51 0:00 /usr/bin/python /usr/bin/glance-api /home/jsuh/glance-api.conf
root 20039 6.0 0.1 25188 13356 ? Ss 12:51 0:00 /usr/bin/python /usr/bin/glance-registry /home/jsuh/glance-registry.conf
jsuh 20042 0.0 0.0 3368 744 pts/1 S+ 12:51 0:00 grep glance
The same 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.
In order for your launched glance service to be monitored for unexpected death and respawned if necessary, use the following option:
$ sudo glance-control [service] start –respawn ...
Note that this will cause glance-control itself to remain running. Also note
that deliberately stopped services are not respawned, neither are rapidly bouncing
services (where process death occurred within one second of the last launch).
By default, output from glance services is discarded when launched with glance-control.
In order to capture such output via syslog, use the following option:
$ sudo glance-control –capture-output ...
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-registry.conf
Stopping glance-registry pid: 17611 signal: 15
Starting glance-registry with /home/jpipes/repos/glance/trunk/etc/glance-registry.conf
Reloading a server¶
You can reload a server with the glance-control program, as demonstrated
here:
$> sudo glance-control api reload
Reloading glance-api (pid 18506) with signal(1)
A reload sends a SIGHUP signal to the master process and causes new configuration settings to be picked up without any interruption to the running service (provided neither bind_host or bind_port has changed).