NAME

       job_container.conf - Slurm configuration file for job_container/tmpfs plugin

DESCRIPTION

       job_container.conf   is   an   ASCII   file  which  defines  parameters  used  by  Slurm's
       job_container/tmpfs plugin. The plugin reads the job_container.conf file to find  out  the
       configuration  settings.  Based  on  them  it  constructs a private (or optionally shared)
       filesystem namespace for the job and mounts a list of directories (defaults  to  /tmp  and
       /dev/shm)  inside  it. This gives the job a private view of these directories. These paths
       are mounted inside the location specified by 'BasePath' in  the  job_container.conf  file.
       When  the  job  completes,  the  private  namespace is unmounted and all files therein are
       automatically removed.  To make use of this plugin,  'PrologFlags=Contain'  must  also  be
       present in your slurm.conf file, as shown:

       JobContainerType=job_container/tmpfs
       PrologFlags=Contain

       The file will always be located in the same directory as the slurm.conf.

       If  using  the  job_container.conf file to define a namespace available to nodes the first
       parameter on the line should be NodeName. If configuring a  namespace  without  specifying
       nodes, the first parameter on the line should be BasePath.

       Parameter  names are case insensitive.  Any text following a "#" in the configuration file
       is treated as a comment through the end of that line.  Changes to the  configuration  file
       take effect upon restart of Slurm daemons.

       The  following  job_container.conf  parameters  are defined to control the behavior of the
       job_container/tmpfs plugin.

       AutoBasePath
              This determines if plugin should create the BasePath directory or not.  Set  it  to
              'true'  if  directory  is not pre-created before slurm startup. If set to true, the
              directory is created with permission 0755. Directory is not  deleted  during  slurm
              shutdown.  If  set  to  'false'  or not specified, plugin would expect directory to
              exist. This option can be used on a global or per-line basis.   This  parameter  is
              optional.

       BasePath
              Specify  the  PATH  that the tmpfs plugin should use as a base to mount the private
              directories. This path must be readable and writable  by  the  plugin.  The  plugin
              constructs  a  directory  for  each  job  inside  this path, which is then used for
              mounting. The BasePath gets mounted as 'private' during slurmd  start  and  remains
              mounted  until  shutdown.  The  first  "%h"  within  the  name is replaced with the
              hostname on which the slurmd is running. The first "%n" within the name is replaced
              with  the  Slurm  node  name  on which the slurmd is running. Set PATH to 'none' to
              disable the tmpfs plugin on node subsets when there is a global setting.

              NOTE: The BasePath must be unique  to  each  node.  If  BasePath  is  on  a  shared
              filesystem, you can use "%h" or "%n" to create node-unique directories.

              NOTE:  The  BasePath parameter cannot be set to any of the paths specified by Dirs.
              Using these directories will cause conflicts when trying to mount and  unmount  the
              private directories for the job.

       Dirs   A  list  of  mount points separated with commas to create private mounts for.  This
              parameter is optional and if not specified it defaults to "/tmp,/dev/shm".

              NOTE: /dev/shm has special handling, and instead of a bind mount is always a  fresh
              tmpfs filesystem.

       InitScript
              Specify  fully qualified pathname of an optional initialization script. This script
              is run before the namespace construction of a job. It can be used to make  the  job
              join additional namespaces prior to the construction of /tmp namespace or it can be
              used for any site-specific setup. This parameter is optional.

       NodeName
              A NodeName specification can be used to permit one job_container.conf  file  to  be
              used  for  all  compute nodes in a cluster by specifying the node(s) that each line
              should apply to.  The NodeName specification can use a Slurm hostlist specification
              as shown in the example below. This parameter is optional.

       Shared Specifying   Shared=true  will  propagate  new  mounts  between  the  job  specific
              filesystem namespace and the root filesystem namespace, enable using autofs on  the
              node. This parameter is optional.

NOTES

       If any parameters in job_container.conf are changed while slurm is running, then slurmd on
       the respective nodes will need to be  restarted  for  changes  to  take  effect  (scontrol
       reconfigure  is  not  sufficient).   Additionally  this  can be disruptive to jobs already
       running on the node. So care must be taken to make sure no jobs are running if any changes
       to job_container.conf are deployed.

       Restarting   slurmd   is   safe   and   non-disruptive   to   running  jobs,  as  long  as
       job_container.conf is not changed between restarts in which case above point applies.

EXAMPLE

       /etc/slurm/slurm.conf:
              These are the entries required in slurm.conf to  activate  the  job_container/tmpfs
              plugin.

              JobContainerType=job_container/tmpfs
              PrologFlags=Contain

       /etc/slurm/job_container.conf:
              The  first  sample  file  will  define  1  basepath  for  all  nodes and it will be
              automatically created.
              AutoBasePath=true
              BasePath=/var/nvme/storage

              The second sample file will  define  2  basepaths.   The  first  will  only  be  on
              largemem[1-2]  and  it  will  be automatically created.  The second will only be on
              gpu[1-10], will be expected to exist and will run an initscript before each job.
              NodeName=largemem[1-2] AutoBasePath=true BasePath=/var/nvme/storage_a
              NodeName=gpu[1-10] BasePath=/var/nvme/storage_b InitScript=/etc/slurm/init.sh

              The third  sample  file  will  Define  1  basepath  that  will  be  on  all  nodes,
              automatically created, with /tmp and /var/tmp as private mounts.
              AutoBasePath=true
              BasePath=/var/nvme/storage Dirs=/tmp,/var/tmp

COPYING

       Copyright  (C)  2021 Regents of the University of California Produced at Lawrence Berkeley
       National Laboratory
       Copyright (C) 2021-2022 SchedMD LLC.

       This  file  is  part  of  Slurm,  a  resource  management  program.   For   details,   see
       <https://slurm.schedmd.com/>.

       Slurm  is  free  software; you can redistribute it and/or modify it under the terms of the
       GNU General Public License as published by the Free Software Foundation; either version  2
       of the License, or (at your option) any later version.

       Slurm is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
       even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See  the
       GNU General Public License for more details.

SEE ALSO

       slurm.conf(5)