groups.conf (5)

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.

[\fIGroup_source\fP] 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 automatically.

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.

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

Simple configuration file for local groups and slurm partitions binding.

\fIgroups.conf\fP

[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

/etc/clustershell/groups.conf

System-wide external node groups configuration file.

/etc/clustershell/groups.conf.d/

Recommended directory for additional configuration files.

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

http://clustershell.sourceforge.net/

Stephane Thiell, CEA DAM <[email protected]>

CeCILL-C V1