How do I access grid files from within images?

I have a container and within that container, I want to be able to access arbitrary grid-based storage like

TFile *f2 = TFile::Open("root://ccxrdatlastpc.in2p3.fr:1094//pnfs/in2p3.fr/data/atlas/atlasdatadisk/rucio/mc16_13TeV/e9/57/DAOD_JETM1.20147497._000159.pool.root.1")

How do I do this? Do images already exist with this capability?

Hi Sam,

I’m not entirely sure, but I think not… :frowning:

The analysis images (both for AnalysisBase and AthAnalysis) contain all the I/O libraries that ROOT needs to access files locally or remotely when running on the grid. But my understanding is that the containers running on the grid just inherit the authentication tokens necessary for those libraries, from the grid runners. The images themselves do not have commands like voms-proxy-init installed in them.

I’m afraid this is not the right forum to follow up about this. We’d need ALRB and Rucio experts to give their input on what all needs to be put into an image so that it would be able to perform the authentication for the above example command to work.

Cheers,
Attila