AttributesSubcommittee

Introduction

This is the final report from the Integration subcommittee tasked to resolve pending questions and issues with the OSG information system as it appears in OSG 0.6. Specifically, the group was asked to:

• Ensure the presently published OSG attributes are well understood and documented.
• Identify subset of neccessary attributes that must be advertised that othwerwise would generate a trouble ticket, ensuring integrity of the OSG environment.
• Identify user tools and pointers to documentation sufficient to meet the needs of VOs - i.e. customers of the information.
• Identify advanced methods needed and potential next steps for publishing more complicated cluster and storage configurations.

Membership

• Anand, Suchandra, Steven, David with contributed remarks from Ted, Horst, Marco, John U and others.

Meetings

• MinutesAttributesMar13
• MinutesAttributesMar20
• MinutesAttributesMar27
• MinutesAttributesApr3
• Further discussions can be found in integration meetings at MeetingMinutes.

OSG attribute meanings and critical attributes

The GIP Attributes review page has tables of OSG-GIP attributes that have been reviewed by the subcommittee and discussed in OSG integration meetings. A subset of these have been identified as critical to defining the OSG information environment. Operationally, incorrect or missing critical attributes should be flagged and followed up opertionally (eg. by generating a trouble ticket).

Commentary/guidance on storage semantics

The mandatory storage attribute settings are described here, which was the input to the OSG 0.6 release documentation. Here we review these semantics for each of the four storage models discussed, and point to live instances and services where possible.

1. The Grid3 model
2. The Extended Grid3 model
3. The LCG model
4. The OSG with SRM-based SE model

The first two (Grid3 and Extended Grid3) models do not assume a separate storage element. More information about configuring these type of sites can be found in the Guide to GIP Configuration Questions.

Models 3 & 4 (LCG and OSG with SRM-based SE) tend to assume a SRM based Storage Element. Details about how to configure GIP to publish this information correctly can be found in the SRM section of the Guide to GIP Configuration Questions. Look at passing sites in the storage testing page to see how information is reported by other OSG SEs.

Tools and tips for the OSG information environment

• Tip: See Guide to GIP Configuration Questions
• Tip: to see output produced by the GIP, run $VDT_LOCATION/lcg/libexec/osg-info-wrapper
• Tip: for OSG 0.6.0, to see raw ldif output: $VDT_LOCATION/lcg/var/gip/ldif/
• Tip: for SE best practices from a user's perspective, see https://twiki.grid.iu.edu/twiki/bin/view/Troubleshooting/StorageElementBestPractices
• Tool: $VDT_LOCATION/glite/etc/glite-ce-ce-plugin/glite-ce-info
• Tool: LDAP Browser

Next steps

Discuss here what is being planned moving forward.

• Need to add equivalent of lcg-info-sites for OSG.
• Glue schema 1.3 migration
• Subcluster schema for ReSS.
• Continued improvement of SE information.
• Continued focus on WLCG interoperability: eg., from John Hover, for the estimated time to execute attribute (GlueCEStateEstimatedResponseTime): EGEE has fully-functional PBS (Torque) and LSF plugins, and possibly SGE, but the Condor plugin is still in development, i.e. not really working reliably. The RPM (lcg-info-dynamic-scheduler-generic-1.6.3-1 ) is included in the current glite 3.0 repository, but doesn't seem to be installed by default on a glite-CE.
• Add a standalone GIP pacman package (changes mainly on the configure scripts) ?

References

• GIP documentation in OSG 0.6.
• Guide to GIP Configuration Questions
• OSG GOC storage element testing in the ITB, see here.
• SE best practices, https://twiki.grid.iu.edu/twiki/bin/view/Troubleshooting/StorageElementBestPractices
• Glue Schema Specification: http://glueschema.forge.cnaf.infn.it/

-- AnandPadmanabhan - 12 Apr 2007
-- RobGardner - 04 Apr 2007