.\" Copyright (C) 2009 Red Hat, Inc. All Rights Reserved. 
.\" Written by Ivana Varekova <varekova@redhat.com> 

.TH CGRULES.CONF  5 2009-03-10 "Linux" "libcgroup Manual"
.SH NAME
cgrules.conf \- libcgroup configuration file 
.SH DESCRIPTION
.B "cgrules.conf"
configuration file is used by
.B libcgroups
to define control groups to which a process belongs.


The file contains a list of rules which assign to a defined group/user a control
group in a subsystem (or control groups in subsystems).

Rules have two formats: 

.in +4n
.nf
<user>               	<controllers>		<destination>
.fi
.nf
<user>:<process name>	<controllers>		<destination>
.fi
.in

Where:

.I user
can be:
.nf
    - a user name
    - a group name with @group syntax
    - the wildcard '*', for any user or group
    - '%', which is equivalent to "ditto" (useful for 
      multi-line rules where different cgroups need to be 
      specified for various hierarchies for a single user)
.fi

.I process name
is optional and it can be:
.nf
    - a process name
    - a full command path of a process
.fi

.I controllers
can be:
.nf
    - comma separated controller names (no spaces) or 
    - * (for all mounted controllers)
.fi

.I destination
can be:
.nf
    - path relative to the controller hierarchy (ex. pgrp1/gid1/uid1)
    - following strings called "\fBtemplates\fR" and will get expanded

          %u     uid
          %U     username, uid if name resolving fails
          %g     gid
          %G     group name, gid if name resolving fails
          %p     pid
          %P     process name, pid if name not available

          '\\' can be used to escape '%'
.fi
First rule which matches the criteria will be executed.

Any text starting with '#' is considered as a start of comment line and is
ignored.

If the
.I destination
contains
.B template
string, the control group can be created on-fly. In time when some process wants
to use the template rule which leads to control group (see
\fBcgexec\fR (1)) and the control group does not exist, the group is created. The
template control group parameters can be specified in
.B cgconfig.conf
configuration file. See (\fBcgconfig.conf\fR (5)).
If the template definition is not found there created group have default
kernel setting.

To create a hierarchy of configuration files, use \fB/etc/cgrules.d\fR directory.

.SH EXAMPLES
.nf
student         devices         /usergroup/students
.fi
Student's processes in the 'devices' subsystem belong to the control
group /usergroup/students.

.nf
student:cp       devices         /usergroup/students/cp
.fi
When student executes 'cp' command, the processes in the 'devices' subsystem
belong to the control group /usergroup/students/cp.

.nf
@admin           *              admingroup/
.fi
Processes started by anybody from admin group no matter in what subsystem belong
to the control group admingroup/.

.nf
peter           cpu             test1/
%               memory          test2/
.fi
The first line says Peter's task for cpu controller belongs to test1 control
group. The second one says Peter's tasks for memory controller belong to test2/
control group.

.nf 
*               *               default/ 
.fi
All processes in any subsystem belong to the control group default/. Since
the earliest matched rule is applied, it makes sense to have this line
at the end of the list. It will put a task which was not mentioned in the
previous rules to default/ control group.

.nf
@students	cpu,cpuacct	students/%u
.fi
Processes in cpu and cpuacct subsystems started by anybody from students group
belong to group students/name. Where "name" is user name of owner of the
process.



.SH FILES
.LP
.PD .1v
.TP 20
.B /etc/cgrules.conf
.RS 6
default libcgroup configuration file
.RE
.TP 20
.B /etc/cgrules.d
.RS 6
default libcgroup configuration files directory
.RE
.PD


.SH SEE ALSO
cgconfig.conf (5), cgclassify (1), cgred.conf (5), cgrules.d (5)

.SH BUGS