MinutesSRMApr18

Introduction

• Background: _As discussed during the facilities meeting yesterday, we will have a special meeting dedicated to SRM V2.2 issues.
• Coordinates: Friday, 4/18, 11:00am Eastern, Phone: (605) 475-6000, Access code: 735188, Dial "*6" to mute/un-mute* (PLEASE mute when not speaking, thanks!)
• Attending: John Brunelle, Wei, Paul, Bob, Rob, Charles, Marco, Shawn, Kaushik, We=njing, Tadashi, Wensheng, Michael, Hiro

Experience with SRM V2.2 at AGLT2

• Started transition. AGLT_SRM site was defined in ToA already. Had been using this for ntuple and AODs. (Will transition this to ATLASDATADISK).
• Had been using 20TB gridftp endpoint AGLT2 readonly.
• New location in dCache - high performance storage pools. ATLASMCDISK area brought up with space tokesn - plan was to migrate the gridftp data. Wenjing used srmcp.
• Afterwards would update LRC. And change the replica location in central catalogs - to use AGLT2_SRM from AGLT2.
• MIgration time was long - srmcp picky and slow.
• There was also a network problem as well - subnets at BNL not available.
• Right now everything is pointing to an srm v2.2 compliant area, but without space tokens.
• 100K files. uses srmcp and a list. during the copy srmcp would get "reset" every 7K files. gridftp server to one of 4 pools, so performance was good. failures could be recovered, but by hand. for the transfers - FTS may be used, though did not
• Change site location in central catalogs. dq2-register-replica for datasets. dq2-delete-replicas to delete the old site registration.
• PANDA will monitor only ATLASMCDISK.
• For moving outputs - need to use a space-token-aware command.
• Paul - pilot can only use lcg-cp site mover for space tokens.
• glite 3.1.

Wei

• Migration issues to ATLASMCDISK and ATLASDATADISK - re-subscribe data?
• Keep the old site? Tadashi thinks Panda can handle this - both locations kept in the SE list. Gradual migration. Since all sites are using a single LRC, shouldn't be a problem.

Data migration issues

• Discussed gradual migration.
• No data presently needs to go into ATLASMCDISK.

Pilot/Panda issues

• PandaMover will need to be fixed.
• For reading, you can continue to use dccp.
• PandaMover for xrootd - Wei can provide a tool, to avoid an srm interface and write directly.
• In pilot3, there are two movers for reading and writing.
• Paul - there are possible conflicts due to regional hard-coded settings.
• Charles would like to review the lcg-cp dependencies.

Plans/schedule for completion of all T2 migration by April 25th

• All comfortable with gradual migration
• Sites setup atlasmcdisk, atlasdatadisk.
• Sites should let panda team know when the migration is ready. Need to make switch in site services.
• Panda mover needs to updated for space tokens.
• Target - have endpoints ready by April 25.
• But, need to get lcg-cp and panda mover and panda data mover changes.
• glite-url-copy, deprecated.

Aside - pilot2/pilot3

• Would like to switch to pilot3 for every site.
• Since condor-g probs resolved, now ready to switch
• aglt2, swt2, ou, slac running pilot3
• mw, ne need to make switch
• Torre needs to setup site in pilot3
• pilot2/pilot3 jobs can run simultaneously.
• What about ATLASENDUSER? Yes, set this one up too - where Pathena.

AOB

• Need clarification about storage categories. https://twiki.cern.ch/twiki/bin/view/Atlas/SpaceTokens

-- RobertGardner - 18 Apr 2008