r2 - 24 Jun 2008 - 12:46:34 - RobertGardnerYou are here: TWiki >  Admins Web > LFCMeetJune24



  • Meeting of the sub-committee to address LFC migration in the US cloud.
  • Coordinates:
    • Tuesday, June 24, 10am Central/5pm CERN
    • Phone: (605) 475-6000, Access code: 735188; Dial *6 to mute/un-mute.
  • Background: SubCommitteeLFC
  • Attending: Torre, Charles, Rob, Patrick, John, Armen, Alexei, Hiro, Xin, Dantong


  • Deployment model question - a single LFC for everyone (Tier 1/2/3)?
    • Charles: Argument for keeping LFC close to the site - not-centralized. John in agreement. Patrick: a Tier2 has the best view of its own storage, best for consistency checks.
    • John: LFC is an easy install for a Tier2, not necessarily a Tier 3.
    • Patrick: suspect we'll converge on a model of Tier2's handling the cataloging for a Tier3. One issue is a Tier3 may not want to set aside hardware for an LFC, especially that it might be handled.
    • Scaling issues - very interesting to see how well LFC performs at BNL.
    • Alexei - would prefer a federated model for Tier2+3 - the Tier2 provides everything; this has been shown already to work in the EU clouds for over a year (a single Tier 1 hosting catalog and DQ2 services for many Tier2s). Concerned about the number of catalogs if Tier3's begin setting these up - adding 20 catalogs for example, and the effects on DQ2 client tools.
    • John: LFC developers have tested at the scale of 40M.
  • Pilot integration:
    • Data mover will need to be modified to support LFC.
  • Database backend issue:
    • Torre is concerned about using Oracle at the Tier1 while using Mysql at the Tier2s. Doubling required expertise, support issues for Tier 2's given the Tier 1 uses Oracle.
    • Dantong notes that using Oracle as a backend because its an Oracle cluster. LCG is officially supporting Oracle.
    • Should BNL support a Mysql backend - for operational issues? John thinks not for the time being, that as far as LFC is concerned the database backend is opaque.
    • Question about Mysql support from the LFC developers. Dantong claimed BNL has asked for continued support; we need a clear statement about the nature of this support however.

Action items

  • Follow-up with Paul on data mover (Torre)
  • Preparation of BNL test site which uses OSG 1.0 wn-client (Xin, John)
  • Migration recipe for LRC to LFC conversion (Hiro)
  • Setup a Tier2 w/ LFC and Mysql backend to develop experience at the Tier2s
    • UC (Charles)
    • UTA-DPCC (Patrick)


  • Hiro pointed out the problem with supporting root files in the same catalog as the "normal" grid-resident files. These root files are not visible to the grid - do they belong there? Is there a hack that can be made to continue to support (local) cataloging for PROOF farms? Create a separate catalog?
  • We did not converge on a solution for this problem - will need to find a solution.
  • Did not converge on a migration date for the full production LRC at BNL - this depends on results of the BNL test site.


  • Next meeting: July 8. Hiro out of town but will provide Migration recipe in advance.

-- RobertGardner - 20 Jun 2008

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