Slurm

Slurm (also referred as Slurm Workload Manager or slurm-llnl) is an open-source workload manager designed for Linux clusters of all sizes, used by many of the world's supercomputers and computer clusters. It provides three key functions. First it allocates exclusive and/or non-exclusive access to resources (computer nodes) to users for some duration of time so they can perform work. Second, it provides a framework for starting, executing, and monitoring work (typically a parallel job) on a set of allocated nodes. Finally, it arbitrates contention for resources by managing a queue of pending work.

Installation

Install the slurm-llnl package (or slurm-llnl-git^AUR). It pulls in munge (), an authentication service, as a dependency. It is started as a requirement through slurmd's systemd service and encrypts the connection between the various hosts. Therefore make sure that all nodes in your cluster have the same key in /etc/munge/munge.key.

The package itself has many more optional dependencies, though Slurm has to be recompiled to make use of them, after they have been installed.

Setup

The configuration files for slurm-llnl reside under /etc/slurm-llnl. Prior to starting any slurm-services, it has to be configured properly by creating a configuration file at /etc/slurm-llnl/slurm.conf. Client and server may use the same configuration file, which can either be generated at the official website or by copying to /etc/slurm-llnl/slurm.conf and adapting it to ones liking.

By default the Slurm user, which was introduced to your system in the installation process, has as UID and GID, this simplifies the setup on multiple systems. UID and GID matches the one used in Debian, therefore they may be used side-by-side, but remember that binaries are not in the same directories on each and every distribution.

Client (compute node) configuration

On the client-side one may now safely start/enable .

Server (head node) configuration

Start/enable .

Additionally you may want to start/enable slurmdbd.service, which handles a SQL database for easier management thereby logging somewhat essential process information.

Note: Additional arguments may be passed to the program by adapting /etc/default/slurm-llnl though still utilizing the power of systemd. This file is handled as the environment file for the various services and simply passes any arguments on to the program.

Troubleshooting

Services fail to start on boot

If or fail to start at boot but work fine when manually started, then the service may be trying to start before a network connection has been established. To verify this, add the lines associated with the failing service from below to the file:

SlurmctldDebug=info
SlurmctldLogFile=/var/log/slurm-llnl/slurmctld.log
SlurmdDebug=info
SlurmdLogFile=/var/log/slurm-llnl/slurmd.log

Then, check the associated log file. If you notice the fatal exception mentions , then you may want to extend the unit so that it waits for a valid network connection via network-online.target.

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