Apptainer/Singularity at LRZ
What is Apptainer/Singularity
Container solution in user space. (Singularity, Apptainer)
Getting started ...
Please check the different spack version (spack/24.4.0 is not everywhere default, yet, maybe)! And check also our extfiles (see below)!
(> module sw spack/24.4.0) (> module use /lrz/sys/share/modules/extfiles) > module av singularity # or, singularityce ----------------------- /lrz/sys/share/modules/extfiles --------------------------- singularity/3.8.3 singularity/4.0.1_sylabs > module av apptainer ---------------------- /lrz/sys/share/modules/extfiles ---------------------------- apptainer/1.3.1
Mounting sif or sqfs file fails as that is not permitted by the OS. 
Be aware that using the files naively will cause creation of temporary sandboxes, which fill SCRATCH (or other directories) So, sandboxing before is maybe the better solution!
Please use unsquashfs from the squashfs module:
> module av squashfs ----------------------- ........................ --------------------------- squashfs/...
Currently, there does not exist any direct singularity-support in Slurm, generally!
Usage
That's a "hello world" equivalent. If you want to provide a more intelligent example, we would appreciate.
> singularity build lolcow.sif library://sylabs-jms/testing/lolcow
INFO: Starting build...
INFO: Downloading library image
87.9MiB / 87.9MiB [============================================================================================================] 100 % 14.2 MiB/s 0s
INFO: Verifying bootstrap image /dss/dsshome1/........../.singularity/cache/library/sha256.5022b5e7c7249c40119a875c1ace0700ced4099e077acc75d0132190254563a4
WARNING: integrity: signature not found for object group 1
WARNING: Bootstrap image could not be verified, but build will continue.
INFO: Creating SIF file...
INFO: Build complete: lolcow.sif
> ls
lolcow.sif
> singularity run lolcow.sif
INFO: Converting SIF file to temporary sandbox...
_______________________________________
/ You are a bundle of energy, always on \
\ the go. /
---------------------------------------
\ ^__^
\ (oo)\_______
(__)\ )\/\
||----w |
|| ||
INFO: Cleaning up image...