Summary and Schedule
This lesson loads software from EESSI, a shared stack of scientific builds. You select a build with a module. You do not compile a private copy into your home directory.
The same Python is available on the cluster and in the EESSI client container. The container has no queue. A long run still belongs on the cluster.
| Setup Instructions | Download files required for the lesson | |
| Duration: 00h 00m | 1. A shared software stack |
Why do you load a module instead of installing a program into your home
directory? What does the EESSI init script print, and which part of that printout can differ? ::: |
| Duration: 00h 25m | 2. Finding and loading a module |
Which command lists only the modules you can load right now, and which
command searches the rest? Which Python module is the EESSI 2025.06 default, and what does python3 --version print?Where do you load QCG-PilotJob if module spider
cannot find it in EESSI?::: |
| Duration: 01h 05m | 3. The EESSI client container |
How do you get the EESSI 2025.06 stack when you have no cluster
login? What do $EESSI_VERSION and
$EESSI_CVMFS_REPO print, and what does the CPU line
mean?Which commands are missing inside the client? ::: |
| Duration: 01h 35m | Finish |
The actual schedule may vary slightly depending on the topics and exercises chosen by the instructor.
You need a terminal. You need one of the three places below. You do not need all three.
Snellius
Snellius is the Dutch national supercomputer. SURF sends the account mail. The public description is at https://www.surf.nl/en/services/compute/snellius-the-national-supercomputer.
Sign in to the SURF user portal before the first SSH login. If the network you are on is not trusted, the welcome mail names a door node. Use that host.
module load 2025 selects the 2025 stack. The first
episode has the load lines for each machine.
The course cluster
Your trainer sends a setup link and a welcome note. The note has the address and the login. There is one login node.
MANAGER is the address in the welcome note. It is not
snellius.surf.nl. module load 2025 loads EESSI
2025.06 on this cluster. The first episode’s tab has the exact
lines.
The EESSI client, when you have no cluster
You need Apptainer 1.0 or newer, with --fusemount
support. Access is documented at https://www.eessi.io/isc26-tutorial/getting-access/ and
day-to-day use at https://www.eessi.io/isc26-tutorial/usage/.
The client mounts the same CVMFS repository the stack is published on. It does not start a queue.
You do not need the client container when you are on the course
cluster. module load 2025 loads EESSI 2025.06.
After the init script from that tab:
python3 --version prints Python 3.13.5. The
first launch downloads the image and can take a few minutes. Later
launches are shorter.
No queue in the container
The container has no sbatch and no squeue.
Use it for these software episodes. Use Snellius or the course cluster
when the work has to wait in a queue.