    sattach [\fIoptions\fP] <jobid.stepid>
    .SH "DESCRIPTION"
    .LP
    sattach attaches to a running Slurm job step.  By attaching, it makes available
    the IO streams of all of the tasks of a running Slurm job step. It is also
    suitable for use with a parallel debugger like TotalView. It cannot be used to
    attach directly to extern or batch steps since the IO channels of these steps
    are not set or directly forwarded to a file.

    .SH "OPTIONS"
    .LP

    .TP
    \fB\-\-error\-filter\fR[=]<\fItask number\fR>
    .PD
    Only transmit standard input to a single task, or print the standard output
    or standard error from a single task.  The filtering is performed locally in
    sattach.
    .IP

    .TP
    \fB\-h\fR, \fB\-\-help\fR
    Display help information and exit.
    .IP

    .TP
    \fB\-\-input\-filter\fR[=]<\fItask number\fR>
    .PD
    Only transmit standard input to a single task, or print the standard output
    or standard error from a single task.  The filtering is performed locally in
    sattach.
    .IP

    .TP
    \fB\-l\fR, \fB\-\-label\fR
    Prepend each line of task standard output or standard error with the task
    number of its origin.
    .IP

    .TP
    \fB\-\-layout\fR
    Contacts the slurmctld to obtain the task layout information for the job step,
    prints the task layout information, and then exits without attaching to the
    job step.
    .IP

    .TP
    \fB\-\-output\-filter\fR[=]<\fItask number\fR>
    .PD
    Only transmit standard input to a single task, or print the standard output
    or standard error from a single task.  The filtering is performed locally in
    sattach.
    Suppress informational messages from sattach. Errors will still be displayed.
    .IP

    .TP
    \fB\-u\fR, \fB\-\-usage\fR
    Display brief usage message and exit.
    .IP

    .TP
    \fB\-V\fR, \fB\-\-version\fR
    Display Slurm version number and exit.
    .IP

    .TP
    \fB\-v\fR, \fB\-\-verbose\fR
    Increase the verbosity of sattach's informational messages.  Multiple
    '\fB\-v\fR's will further increase sattach's verbosity.
    .IP

    .SH "PERFORMANCE"
    .PP
    Executing \fBsattach\fR sends a remote procedure call to \fBslurmctld\fR. If
    enough calls from \fBsattach\fR or other Slurm client commands that send remote
    procedure calls to the \fBslurmctld\fR daemon come in at once, it can result in
    a degradation of performance of the \fBslurmctld\fR daemon, possibly resulting
    in a denial of service.
    .PP
    Do not run \fBsattach\fR or other Slurm client commands that send remote
    procedure calls to \fBslurmctld\fR from loops in shell scripts or other
    programs. Ensure that programs limit calls to \fBsattach\fR to the minimum
    necessary for the information you are trying to gather.

    .SH "INPUT ENVIRONMENT VARIABLES"
    .PP
    Upon startup, salloc will read and handle the options set in the following
    environment variables.  Note: Command line options always override environment
    variables settings.

    .TP
    \fBSLURM_CONF\fR
    The location of the Slurm configuration file.
    .IP

    .TP
    \fBSLURM_DEBUG_FLAGS\fR
    Specify debug flags for sattach to use. See DebugFlags in the
    \fBslurm.conf\fR(5) man page for a full list of flags. The environment
    variable takes precedence over the setting in the slurm.conf.
    .IP

    .TP
    \fBSLURM_EXIT_ERROR\fR

    .TP
    Limit the output to the 5th task of job 65386, step 15:
    .IP
    .nf
    $ sattach \-\-output\-filter 5 65386.15
    .fi

    .SH "COPYING"
    Copyright (C) 2006\-2007 The Regents of the University of California.
    Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
    .br
    Copyright (C) 2008\-2009 Lawrence Livermore National Security.
    .br
    Copyright (C) 2010\-2022 SchedMD LLC.
    .LP
    This file is part of Slurm, a resource management program.
    For details, see <https://slurm.schedmd.com/>.
    .LP
    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.
    .LP
    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.

    .SH "SEE ALSO"
    .LP
    \fBsinfo\fR(1), \fBsalloc\fR(1), \fBsbatch\fR(1), \fBsqueue\fR(1),
    \fBscancel\fR(1), \fBscontrol\fR(1),
    \fBslurm.conf\fR(5), \fBsched_setaffinity\fR (2), \fBnuma\fR (3)