How to source a specific LCG release that isn't showing up in the software stack?

Hi all,

I am completely new to SWAN, so I apologize if this question is obvious. I’ve come across something in my analysis which requires a functionality found in ROOT v6.28. Instead of trying to find a compatible CMSSW release or re-installing ROOT locally, I thought it might be easiest just to use SWAN with ROOT v6.28-compatible LCG release.

I looked through the LCG info site for the specific ROOT v6.28 package and saw that it’s available for the LCG releases dev4, 103swan, 103_LHCB_Core, 103_LHCB_7, 103cuda, and 103. However, when I attempt to configure my SWAN environment, I don’t see any of those releases available under the software stack (even after scrolling down through the options):

It seems as though I’m only able to source releases up to 102. Is there some way to use the releases I listed above as a general user? Maybe they’re just not available for general use yet, but I’m not sure. Any clarification would be appreciated!


Dear Amitav,

LCG 103, which has ROOT 6.28, was just finished. We will provide it soon in SWAN (probably in the next two weeks) but it needs to go through some testing first.

Instead, you can select the Bleeding Edge software stack, which has ROOT master (i.e. 6.29). That one should include any feature / bug fix that is also in 6.28.

And welcome to SWAN!



Dear Enric,

Thank you for the quick response, that makes sense and is completely understandable :slight_smile:

I’ve successfully configured a new environment with the Bleeding Edge software stack and everything works as expected. Thanks again, SWAN is really very useful!