RAL Tier1 Experiments Liaison Meeting

Wednesday 24 May 2023, 12:30 → 14:30 Europe/London

Access Grid (RAL R89)

13:00 Major Incidents Changes

1 Summary of Operational Status and Issues

Speakers: Brian Davies (Lancaster University (GB)), Darren Moore (Science and Technology Facilities Council STFC (GB)), Kieran Howlett (STFC RAL)

Weekly Report 24 May 2023.docx

Weekly Report 24 May 2023.pdf

2 GGUS /RT Tickets

https://tinyurl.com/T1-GGUS-Open
https://tinyurl.com/T1-GGUS-Closed

3 Site Availability

https://lcgwww.gridpp.rl.ac.uk/utils/availchart/

https://cms-site-readiness.web.cern.ch/cms-site-readiness/SiteReadiness/HTML/SiteReadinessReport.html#T1_UK_RAL

http://hammercloud.cern.ch/hc/app/atlas/siteoverview/?site=RAL-LCG2&startTime=2020-01-29&endTime=2020-02-06&templateType=isGolden

13:05 Experiment Operational Issues

4 VO Liaison CMS

Speaker: Katy Ellis (Science and Technology Facilities Council STFC (GB))

From last week - problems with Echo went away after Tuesday 16th May. No changes made since then on e.g. vReads. New hardware installation and re-weighting on Echo continues.

Tape REST API - Katy tested functionally (not at scale) and davs transfers worked as expected. CMS not planning to switch to davs soon...we will continue to use root transfers only with Antares for now.

Concerning the 'access' test that CMS applied to Antares, CMS have decided that the current situation is acceptable and the tests have been made green. I updated the Jira, but sounds like Tom Byrne is still keeping the issue in mind.

5 VO-Liaison ATLAS

Speakers: James William Walder (Science and Technology Facilities Council STFC (GB)), Jyoti Prakash Biswal (Rutherford Appleton Laboratory)

 

https://stfc.atlassian.net/browse/GS-131: Jobs failing with: failed to close file descriptor: bad file descriptor 

(peak rate ~ 200 jobs per day, typically user analysis; observeed elsewhere at only pic, IFAE). 

 

TAPE REST API:

• Enabled for production for MCTAPE activities

SRR is not correct for atlas storage values:

https://s3.echo.stfc.ac.uk/srr/storagesummary.json 

• Fortunately for RAL, we don't use that. 

 

ATLAS Tokens:

• Less advanced status to CMS; but starting to become more active
• LFNs using token access are likely (but not yet definite) to use a flat namespace across sites.
  • I.e. we will need to do some name-to-name mapping when a token request comes in to the actual PFN 

 

I would like us to engage in pack-marking / flow studies; which would mean to start sending flow data to the JISC flow collector ?

6 VO Liaison LHCb

Speaker: Alexander Rogovskiy (Rutherford Appleton Laboratory)

Tickets:

• Request to switch to host certificate for LHCb vobox
  • It's with the security team
• Slow stat calls (checksums)
  • No update
• Network issue
  • No update
• Vector read
  • Test environment (xcache v5.5.4 and patched xrootd-ceph-buffered) was set up on lcg2268, looks OK so far

Operational issues:

• LHCb drained a little bit on Monday after a but introduced by LHCb DIRAC update
  • Fixed within several hours.

7 VO Liaison LSST

Speaker: Timothy John Noble (Science and Technology Facilities Council STFC (GB))

8 VO Liaison Others

13:31 AOB

9 Any other Business

Speakers: Brian Davies (Lancaster University (GB)), Darren Moore (Science and Technology Facilities Council STFC (GB))