Hi,
A global LFC means the VO has one catalogue in the whole Grid which references all its files, so any user in the VO can simply query the info system and use that catalogue. (And if the query returns more than one global LFC then someone has messed up! Gstat 1 used to flag that as an error, I'm not sure if gstat 2 does. [1]) If the VO hasn't made any other decision then a global LFC is indeed the right choice.
A local LFC is anything that isn't a global LFC - the usage would be defined by the VO. There can be any number of local LFCs so although you can also get them from the info system you would generally need some external way to decide which one to use for any given case. You could in principle have local LFCs for specific purposes and a global LFC for everything else, although I don't know if anyone does that.
Stephen
[1] It seems there are quite a few VOs with multiple global LFCs ...
ldapsearch -x -h lcg-bdii.cern.ch -p 2170 -b o=grid glueservicetype=lcg-file-catalog | grep Owner: | sort | uniq -c -d
2 GlueServiceOwner: ams02.cern.ch
2 GlueServiceOwner: argo
2 GlueServiceOwner: babar
2 GlueServiceOwner: beapps
2 GlueServiceOwner: betest
2 GlueServiceOwner: bio
2 GlueServiceOwner: cdf
2 GlueServiceOwner: compassit
2 GlueServiceOwner: compchem
2 GlueServiceOwner: comput-er.it
2 GlueServiceOwner: cyclops
2 GlueServiceOwner: enea
2 GlueServiceOwner: enmr.eu
2 GlueServiceOwner: eticsproject.eu
2 GlueServiceOwner: euchina
2 GlueServiceOwner: euindia
2 GlueServiceOwner: glast.org
2 GlueServiceOwner: gridit
2 GlueServiceOwner: gridmosi.ici.ro
2 GlueServiceOwner: inaf
2 GlueServiceOwner: infngrid
2 GlueServiceOwner: ingv
2 GlueServiceOwner: libi
2 GlueServiceOwner: pacs.infn.it
2 GlueServiceOwner: pamela
2 GlueServiceOwner: planck
2 GlueServiceOwner: seismo.see-grid-sci.eu
3 GlueServiceOwner: sgdemo
2 GlueServiceOwner: superbvo.org
2 GlueServiceOwner: theophys
2 GlueServiceOwner: tps.infn.it
2 GlueServiceOwner: trgrida
2 GlueServiceOwner: trgridb
2 GlueServiceOwner: trgridc
2 GlueServiceOwner: trgridd
2 GlueServiceOwner: trgride
2 GlueServiceOwner: trgridf
2 GlueServiceOwner: trgridg
2 GlueServiceOwner: virgo
From: Testbed Support for GridPP member institutes [mailto:[log in to unmask]] On Behalf Of Sam Skipsey
Sent: 13 December 2011 16:37
To: [log in to unmask]
Subject: Re: [TB-SUPPORT] Local versus global LFC
Basically, yes. (Although the documentation is not precisely clear on this, and the various interstitial implementations of LFCs - like ATLAS's tiered model with LFCs for each T1-region - confuse the interpretation.)
Sam
On 13 December 2011 16:32, John Gordon <[log in to unmask]> wrote:
Surely a local LFC shows you the files at your site and a global one files everywhere.
-----Original Message-----
From: Testbed Support for GridPP member institutes [mailto:[log in to unmask]] On Behalf Of Christopher J.Walker
Sent: 13 December 2011 16:26
To: [log in to unmask]
Subject: Local versus global LFC
What's the difference between a local and global LFC. Is it only that
the latter is published in the BDII?
Or, to be more specific, shouldn't the LFC setup for snoplus be a global
one?
Chris
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