Create and configure Prolog and Epilog scripts

In a Slurm environment, prolog and epilog scripts are tools that run automatically at the start (prolog) and end (epilog) of every job. You can use these scripts for tasks such as preparing the environment or cleaning up after a job. This guide shows you how to deploy and configure these scripts in SUNK using Kubernetes ConfigMaps, so you can standardize per-job setup and teardown across your cluster. First, you create separate ConfigMaps for your prolog and epilog scripts. Each ConfigMap should contain all the scripts you plan to use. Then, you configure SUNK to use the scripts in the ConfigMaps. After you complete this guide, your SUNK deployment runs your prolog before each job and your epilog after each job.

Create a prolog ConfigMap

Consider this example prolog script, which runs before every job.

#!/usr/bin/env bash
set -e

echo "Prolog test executed"

Convert that script into a Kubernetes ConfigMap, like this:

apiVersion: v1
kind: ConfigMap
metadata:
  name: slurm-prolog
data:
  prolog-test.sh: |
    #!/usr/bin/env bash
    set -e

    echo "Prolog test executed"

Replace prolog-test.sh with your script’s name and the content with your actual script. Save this YAML as slurm-prolog-configmap.yaml. Now apply the ConfigMap to your Kubernetes cluster:

kubectl apply -f slurm-prolog-configmap.yaml

This step creates the ConfigMap in your cluster, but doesn’t activate it in SUNK yet. You activate it in Configure SUNK to use the scripts.

Create an epilog ConfigMap

Creating an epilog ConfigMap is similar to creating the prolog. Here’s an example epilog script that runs after every job:

#!/usr/bin/env bash
set -e

echo "Epilog test executed"

Convert that script into a Kubernetes ConfigMap, like this:

apiVersion: v1
kind: ConfigMap
metadata:
  name: slurm-epilog
data:
  epilog-test.sh: |
    #!/usr/bin/env bash
    set -e

    echo "Epilog test executed"

Replace epilog-test.sh with your script’s name and the content with your actual script. Save this YAML as slurm-epilog-configmap.yaml, then apply the ConfigMap to your Kubernetes cluster:

kubectl apply -f slurm-epilog-configmap.yaml

As before, this creates the ConfigMap, but it’s not yet active in SUNK.

Configure SUNK to use the scripts

After the scripts are in ConfigMaps, configure SUNK to locate them so the slurmd daemon can mount and execute them with each job. In the values.yaml file for the SUNK deployment, set the slurmConfig.slurmd.prologConfigMap and slurmConfig.slurmd.epilogConfigMap values to the ConfigMap names. Here’s an example:

slurmConfig:
  slurmd:
    prologConfigMap: slurm-prolog
    epilogConfigMap: slurm-epilog

Replace slurm-prolog and slurm-epilog with the names of your ConfigMaps. After updating values.yaml, apply the changes to the deployment:

helm upgrade my-sunk-deployment chart/path -f values.yaml

Replace my-sunk-deployment with the name of your Slurm deployment and chart/path with the path to your Slurm chart. From the root of the SUNK repository, the command looks like this:

helm upgrade slurm chart/slurm -f values.yaml

​Create a prolog ConfigMap

​Create an epilog ConfigMap

​Configure SUNK to use the scripts

Create a prolog ConfigMap

Create an epilog ConfigMap

Configure SUNK to use the scripts