I would like to change the all.sitename setting in the xrootd config file to make it unique for each of our EOS instances. As I understand it is used for macaroons for TPC. My impression is that changing it should be fine as long as it is synchronized across all FST/MGMs, and there should be no persistency issues. Can anyone confirm? (Possibly transfers in progress would fail, but that would happen anyway when restarting so doesn’t matter.)
Also what about changing mgmofs.instance, is it fine as long as MGMs agree, or could there be a mismatch with the old value persisted somewhere?
Hi! AFAIK sitename is used only in monitoring and identification so you can change it anytime. If the value is not synchronized on all machine, you will just have monitoring metrics and streams under different names.
The mgmofs.instance it is a functional and written into qdb value and is part of the root of metadata paths for that instance. AFAIK one cannot easily change it, i remember that i wanted at some point to change it and the procedure would have involved changing all values in qdb so i decided that it is not worth it .. but on this subject maybe @esindril could tell us more.
The all.sitename is indeed used for monitoring but also embedded in the macaroon tokens that are handed out by the MGM. Therefore, old macaroons will probably not work with the new MGM if you change this value. As long as you are ok with that I don’t think there are any other side-effect.
The mgm.instancename is indeed more complicated since the name of the instance is embedded in the configuration keys saved in QuarkDB. If you do eos config dump | grep <instancename> you will understand what I mean. Therefore, I would avoid as much as possible to do this change.