sackd(8)

💖 sackd — the Slurm Auth and Cred Kiosk Daemon 💖

okay bestie, welcome to sackd(8), aka the Slurm Auth and Cred Kiosk Daemon — and yeah it's exactly as iconic as that name makes it sound. 🎀

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✨ SYNOPSIS ✨

sackd [OPTIONS...]

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🦋 DESCRIPTION 🦋

So here's the vibe: sackd is the Slurm Auth and Cred Kiosk Daemon. You drop it on login nodes that aren't running slurmd daemons, and it lets those nodes authenticate to the cluster. That's the whole point. Slay.

The program runs as the SlurmUser. 👑

And when you're running in Slurm's "configless" mode? That's the mode where config files get retrieved and written under the /run/slurm/conf directory — unless RUNTIME_DIRECTORY is set, in which case that wins. iykyk.

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🌸 OPTIONS 🌸

• --ca-cert-file <file> — Absolute path to the CA certificate, used for fetching configuration when you're running configless in a TLS enabled cluster. 🔒
• --conf-server host[:port] — Grab configs from slurmctld running at host[:port]. Heads up though, it requires slurmctld support, which you get by setting enable_configless in SlurmctldParameters.
• -D — Run sackd in the foreground, with logging copied to stderr. perfect for watching it do its thing.
• --disable-reconfig — Fetch configurations in configless mode once, but do not register with slurmctld for further reconfiguration updates. one and done, periodt.
• -f config — Read configuration from the specified file.
• -h — Help! Prints a brief summary of command options. 🫶
• --jwks-file <file> — Read the auth/slurm JWKS information from the specified file. Default value is slurm.jwks, chillin' in the same directory as slurm.conf.
• --key-file <file> — Read the auth/slurm authentication key from the specified file. Default value is slurm.key, also hanging out in the same directory as slurm.conf.
• --port number — Port socket number to listen for reconfiguration updates. Super handy when multiple sackds coexist on the same login node (they're roommates, it happens 💅). The default value is SlurmdPort.
• --systemd — Use this when you start it from a systemd unit file.
• -v — Verbose mode. Multiple -v's increase verbosity. stack 'em like bracelets ✨

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🌈 ENVIRONMENT VARIABLES 🌈

These environment variables can be used to override settings compiled into sackd. yes, override. the source code said what it said and these say otherwise. 😌

• ABORT_ON_FATAL — When a fatal error is detected, use abort() instead of exit() to terminate the process. This lets backtraces be captured without recompiling Slurm. big fan.
• RUNTIME_DIRECTORY — Absolute path governing the location for both the configuration cache sackd maintains, and the sack.socket unix socket used to provide authentication services.

If multiple sackds need to be started on the same login node, the RuntimeDirectory systemd unit option should be set to slurm-<clustername>. Systemd v240+ automatically sets RUNTIME_DIRECTORY to /run/$RuntimeDirectory for each sackd service — otherwise it requires manual setting (i.e. via the EnvironmentFile unit option).

If this is not set, the default value is /run/slurm/.

• SACKD_DEBUG — Set the debug level explicitly for syslog and stderr. Valid values are 0-9, or the same string values as the debug options such as SlurmctldDebug in slurm.conf(5).
• SACKD_DISABLE_RECONFIG — Same as --disable-reconfig.
• SACKD_PORT — Same as --port.
• SACKD_STDERR_DEBUG — Set the debug level explicitly for stderr. Valid values are 0-9, or the same string values as the debug options such as SlurmctldDebug in slurm.conf(5).
• SACKD_SYSLOG_DEBUG — Set the debug level explicitly for syslog. Valid values are 0-9, or the same string values as the debug options such as SlurmctldDebug in slurm.conf(5).
• SLURM_CONF — The location of the Slurm configuration file.
• SLURM_DEBUG_FLAGS — Specify debug flags for sackd to use. Peep DebugFlags in the slurm.conf(5) man page for the full list of flags. Heads up: this environment variable takes precedence over the setting in the slurm.conf. 💅

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🔥 SIGNALS 🔥

• SIGINT — sackd will shutdown cleanly. bye bestie, no drama. 🫶
• SIGHUP — sackd will reconfigure. glow-up time ✨
• SIGUSR2 SIGPIPE — This signal is explicitly ignored. not today.

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👑 COPYING 👑

Copyright (C) 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. 😭 (the caps-lock is legal's, not mine)

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🧚 SEE ALSO 🧚

• slurm.conf(5)
• slurmctld(8)

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and that's the whole page, bestie — this was Slurm 26.05, Slurm Auth and Cred Kiosk Daemon, and honestly? it ate. 💖✨🎀🦋🌸💅🫶