GROUPS.CONF(5)						     ClusterShell User Manual						    GROUPS.CONF(5)

NAME

       groups.conf - Configuration file for ClusterShell external node groups

DESCRIPTION

       The  ClusterShell  library obtains node groups configuration options from the system-wide configuration file /etc/clustershell/groups.conf.
       Additional configuration files are also read from the directories set by the groupsdir option, if present.  See the groupsdir option  below
       for further details.

       Configuration files have a format in the style of RFC 822 potentially composed of several sections which may be present in any order. There
       are two types of sections: Main and Group source:

       Main   Global configuration options. There should be only one Main section.

       Group_source

	      The Group_source section(s) define the configuration for each node group source  (or  namespace).  This  configuration  consists	in
	      external commands definition (map, all, list and reverse).

       Only Group_source section(s) are allowed in additional configuration files.

   [Main] OPTIONS
       Configuration parameters of the Main section are described below.

       default
	      Specify  the  default  group source (group namespace) used by the NodeSet parser when the user does not explicitly specify the group
	      source (eg. "@io").

       groupsdir
	      Optional list of directories where the ClusterShell library should look for .conf files which define group sources to use. Each file
	      in  these directories with the .conf suffix should contain one or more Group_source sections as documented in [Group_source] options
	      below. These will be merged with the group sources defined in /etc/clustershell/groups.conf  to  form  the  complete  set  of  group
	      sources that ClusterShell will use. Duplicate Group_source sections are not allowed.  Note: .conf files that are not readable by the
	      current user are ignored.

   [Group_source] OPTIONS
       Configuration parameters of each group source section are described below.

       map    Specify the external shell command used to resolve a group name into a nodeset, list of nodes or list of nodeset (separated by space
	      characters or by carriage returns). The variable $GROUP is replaced before executing the command.

       all    Optional	external  shell command that should return a nodeset, list of nodes or list of nodeset of all nodes for this group source.
	      If not specified, the library will try to resolve all nodes by using the list external command in the same group source followed	by
	      map for each group.

       list   Optional external shell command that should return the list of all groups for this group source (separated by space characters or by
	      carriage returns).

       reverse
	      Optional external shell command used to find the group(s) of a single node. The variable	$NODE  is  previously  replaced.  If  this
	      upcall  is  not specified, the reverse operation is computed in memory by the library from the list and map external calls. Also, if
	      the number of nodes to reverse is greater than the number of available groups, the reverse external  command  is	avoided  automati-
	      cally.

       When  the  library  executes  a	group  source external shell command, the current working directory is previously set to the corresponding
       groupsdir. This allows the use of relative paths for third party files in the command.

       Each external command might return a non-zero return code when the operation is not doable. But if the call return zero, for instance,  for
       a  non-existing	group,	the user will not receive any error when trying to resolve such unknown group.	The desired behaviour is up to the
       system administrator.

RESOURCE USAGE

       All external command results are cached in memory to avoid multiple calls.

EXAMPLES

       Simple configuration file for local groups and slurm partitions binding.

   groups.conf
       [Main]
       default: local
       #groupsdir: /etc/clustershell/groups.conf.d/

       [local]
       map: sed -n 's/^$GROUP:(.*)/1/p' /etc/clustershell/groups
       list: sed -n 's/^([0-9A-Za-z_-]*):.*/1/p' /etc/clustershell/groups

       [slurm]
       map: sinfo -h -o "%N" -p $GROUP
       all: sinfo -h -o "%N"
       list: sinfo -h -o "%P"
       reverse: sinfo -h -N -o "%P" -n $NODE

FILES

       /etc/clustershell/groups.conf

	      System-wide external node groups configuration file.

       /etc/clustershell/groups.conf.d/

	      Recommended directory for additional configuration files.

SEE ALSO

       clush(1), clubak(1), nodeset(1)

       http://clustershell.sourceforge.net/

AUTHOR

       Stephane Thiell, CEA DAM  <stephane.thiell@cea.fr>

COPYRIGHT

       CeCILL-C V1

1.6								    2012-03-31							    GROUPS.CONF(5)