HP XC System Software Administration Guide Version 4.0

If you make any changes, be sure to run the scontrol reconfigure command to update
SLURM with these new settings.
If a user tries to propagate a resource limit with the srun --propagate command, but the
compute node has a lower hard limit than the soft limit, an error message results:
$ srun --propagate=RLIMIT_CORE
.
.
.
Can't propagate RLIMIT_CORE of 100000 from submit host.
For more information, see slurm.conf(5).
15.3 Restricting User Access to Nodes
Although full user authentication is required on every node so that SLURM can launch jobs, and
although this access is beneficial for users who need to debug their applications, it can be a
problem because one user could adversely affect the performance of another user's job: a user
could log on any compute node and steal processor cycles from any job running on that node.
The solution is to restrict users to access to only the nodes that they reserve.
A Pluggable Authentication Module for use with SLURM (pam_slurm) is supplied with HP XC
System Software to verify access. This module is designed to work within the Linux Pluggable
Authentication Module (PAM) framework and confirms with SLURM before authorizing user
access to the local node.
The pam_slurm module is disabled by default, but you can enable it to restrict the use of a
particular node to only one reserved user at a time. Before you enable this module, you must
have a login role defined on at least one node.
During its operation, the cluster_config utility prompts for the option of whether or not to
enable the pam_slurm module and restrict user access to the compute nodes. If you choose to
enable the pam_slurm module, the cluster_config utility confirms which nodes should
have pam_slurm enabled. Make sure that login nodes are removed from the list of these nodes;
otherwise, no one will be able to log in to those nodes.
Restricted access does not apply to the superuser (root user).
If you need to disable the pam_slurm module on a node temporarily, invoke the configpam.pl
unconfigure command. The following example disables node n100 temporarily:
# pdsh -w n100 '/opt/hptc/slurm/sbin/configpam.pl unconfigure'
You must rerun the cluster_config utility to reconfigure permanently which nodes are
enabled with the pam_slurm module.
15.4 Job Accounting
SLURM on the HP XC system can collect job accounting data, store it in a log file, and display
it. The accounting data is available only at the conclusion of a job; you cannot obtain it in real
time while the job is running. You must enable this SLURM job accounting capability to support
LSF on HP XC. LSF is discussed in the next chapter.
This section briefly describes the sacct command, which you can use to display the stored job
accounting data, and discusses how to deconfigure and configure job accounting.
Information on jobs that are invoked with the SLURM srun command is logged automatically
into the job accounting file. Entries in the slurm.conf file enable job accounting and designate
the name of the job accounting log file. The default (and recommended) job accounting log file
is /hptc_cluster/slurm/job/jobacct.log.
178 Managing SLURM