SlurmStack

SlurmStack is a lightweight, automated tool for provisioning a SLURM cluster on OpenStack. Built with Ansible for Rocky Linux 9, this project focuses on providing a minimal, uncomplicated configuration that is easy to modify and run manually. Because it includes a native deployment of slurmrestd, SlurmStack is ideal for setting up a preproduction environment to test or develop services based on the SLURM REST API.

Note

This project is designed for testing and development. Whilst it can be modified for production use, it should not be considered production-ready out of the box.

Consider using Slinky for a more complete production ready solution.

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Installation

Requirements:

• Python 3.11+
• pip

Clone the repository and install the Python/Ansible dependencies:

git clone <repo-url>
cd slurmstack
pip install -e .
ansible-galaxy collection install -r requirements.yml

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Prerequisites

The following must be in place within your OpenStack project before running SlurmStack.

OpenStack credentials:

The OpenStack credentials can be set using a clouds.yaml file, or via the respective environment variables within .env.

To obtain a clouds.yaml file from your OpenStack Horizon dashboard, do the following:

1. Log into Horizon
2. On the left bar, click Identity.
3. Under Identity, click "Application Credentials".
4. Click the "+ Create Application Credentials" button in the top bar.
5. You must provide at least a name.
6. Click "Create Application Credential" at the bottom of the page.
7. Click Download clouds.yaml.

You can also create a clouds.yaml file manually using the provided example:

cp clouds.yaml.example clouds.yaml

Rocky Linux 9 image:

A Rocky Linux 9 image must be available in your OpenStack project. The image name is set via SS_IMAGE. Base images can be found on the Rocky Linux download webpage.

Network:

A network must exist for the OpenStack project, which must be accessible to the VMs. The network name can be set via SS_NETWORK.

Security groups:

One or more security groups must be pre-created in OpenStack and assigned to the VMs via SS_SECGROUP. At a minimum, the groups should allow:

• SSH (port 22) from your control machine
• All internal traffic between cluster nodes

SSH key pair:

An SSH key pair must be registered in OpenStack, and the corresponding private key must be accessible on the machine running SlurmStack. Set the path via SS_ANSIBLE_KEY. Ansible uses this key to connect to the provisioned VMs.

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Run

SlurmStack has two configuration methods available, using an .env file or using the CLI options. Either copy the example environment file and fill in your values as follows:

cp .env.example .env

Or supply the required CLI arguments when running SlurmStack. Note that the CLI arguments take precedence over the .env file. You can supply --help for the full argument reference:

usage: slurmstack.py [-h] [--destroy] [-clu CLUSTER_NAME] [-con CONTROLLER_NAME]
                     [-np NODES_PREFIX] [-nc NODES_COUNT] [-i IMAGE] [-net NETWORK]
                     [-s SECGROUP [SECGROUP ...]] [-cf CONTROLLER_FLAVOUR]
                     [-nf NODES_FLAVOUR] [-cr CLUSTER_IP_RANGE] [-mp MARIADB_PASS]
                     [-k ANSIBLE_KEY]

Provision a Slurm cluster on OpenStack and deploy it with Ansible.

options:
  --destroy                   Tear down all cluster VMs
  -clu, --cluster-name        Name of the Slurm cluster
  -con, --controller-name     Name of the controller VM
  -np,  --nodes-prefix        Prefix for worker node names (e.g. slurm-worker → slurm-worker-1)
  -nc,  --nodes-count         Number of worker nodes
  -i,   --image               OpenStack image name
  -net, --network             OpenStack network name
  -s,   --secgroup            Security group names, comma-separated
  -cf,  --controller-flavour  Flavour for the controller VM
  -nf,  --nodes-flavour       Flavour for worker VMs
  -cr,  --cluster-ip-range    IP range for NFS exports (e.g. 10.0.0.0/24)
  -mp,  --mariadb-pass        MariaDB password for Slurm accounting
  -k,   --ansible-key         Path to SSH private key for Ansible

if ansible fails run: ansible-playbook -i inventory_<cluster-name>.json --private-key /path/to/key playbooks/deploy_nodes.yml