Re: [HTCondor-users] Bug: interactive jobs + custom job attributes + singularity

[Peter Wienemann <wienemann@xxxxxxxxxxxxxxxxxx>]

Dear Greg!

On 06.03.2018 17:52, Greg Thain wrote:
> Right now there is a bug in condor that prevents condor_submit -i from
> entering the correct singularity container. This has just been fixed,
> and will be in an upcoming release.

Is this the patch you are referring to:

https://github.com/htcondor/htcondor/commit/e5b411e9489e3962ad8de3609e83c70b88d0e5c5

> However, singularity doesn't provide an easy mechanism for an arbitrary
> process to enter an existing container.

According to the Singularity documentation, this should be possible
(since version 2.4) without too much hassle using Singularity container
instances (see http://singularity.lbl.gov/docs-instances).

Probably an even more generic option would be to use "nsenter" (see
http://man7.org/linux/man-pages/man1/nsenter.1.html).

> With this patch, condor_submit
> -i will still create a new container for the interactive job, but it
> will be a separate container from the main job. This problem also
> exists for condor_ssh_to_job to a job inside a singularity container.ÂÂ
> A fix for this is a longer-term item.

Reading the future plans of the Singularity developers (see e. g.
https://www.sylabs.io/category/labnotes), it seems that they have
started to re-write everything from scratch for version 3.0 and provide
OCI compatibility. Are there any plans to implement an OCI compatible
container interface in HTCondor, such that it would be easy to switch
between different (OCI compatible) container solutions?

Cheers, Peter