Existing user groups as LSF user groups

User groups already defined in your operating system often reflect existing organizational relationships among users. It is natural to control computer resource access using these existing groups.

You can specify existing UNIX user groups anywhere an LSF user group can be specified.

How LSF recognizes UNIX user groups

Only group members listed in the /etc/group file or the file group.byname NIS map are accepted. The user’s primary group as defined in the /etc/passwd file is ignored.

The first time you specify a UNIX user group, LSF automatically creates an LSF user group with that name, and the group membership is retrieved by getgrnam(3) on the master host at the time mbatchd starts. The membership of the group might be different from the one on another host. Once the LSF user group is created, the corresponding UNIX user group might change, but the membership of the LSF user group is not updated until you reconfigure LSF (badmin). To specify a UNIX user group that has the same name as a user, use a slash (/) immediately after the group name: group_name/.


UNIX group definitions referenced by LSF configuration files must be uniform across all hosts in the cluster. Unexpected results can occur if the UNIX group definitions are not homogeneous across machines.

How LSF resolves users and user groups with the same name

If an individual user and a user group have the same name, LSF assumes that the name refers to the individual user. To specify the group name, append a slash (/) to the group name.

For example, if you have both a user and a group named admin on your system, LSF interprets admin as the name of the user, and admin/ as the name of the group.

Where to use existing user groups

Existing user groups can be used in defining the following parameters in LSF configuration files:

  • USERS in lsb.queues for authorized queue users

  • USER_NAME in lsb.users for user job slot limits

  • USER_SHARES (optional) in lsb.hosts for host partitions or in lsb.queues or lsb.users for queue fairshare policies