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-uinque 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)

November 2022                               Slurm Configuration File                       job_container.conf(5)