I am trying to build a singularity image within which I can act as root using the “–fakeroot” flag. However I get this error:
gercek@cpu288:~$ singularity build --fakeroot iblcore.sif docker://bdgercek/iblcore
FATAL: could not use fakeroot: no mapping entry found in /etc/subgid for gercek
This was not an issue a few months ago when I’d been able to use fakeroot successfully. Did something change about the way Singularity is administered?
Berk
Update: This issue only occurred when I was trying to build on a compute node. When running the same command on the login node () it runs fine.
Additionally, even when I build the container on the login node and attempt to run on compute nodes the fakeroot option fails.
Hi @Berk.Gercek
You are right to be horrified, as you know and everyone should know, computing on the login node is forbidden.
The problem should be solved /etc/subgid was not synchronized on compute nodes, could you try again, and give me a feedback about it?
Yes the command now works just fine (for both singularity build
and singularity run
) on compute nodes as well. Thanks!
So another issue that is related to this, is that when I do run a container with the “fakeroot” option, it takes roughly 10-20x longer to boot into the container than using a vanilla singularity command. The only hint I have as to why this occurs might be this warning:
WARNING: underlay of /etc/localtime required more than 50 (84) bind mounts
which appears each time. Any suggestions here?