RAL Tier1 Experiments Liaison Meeting

Wednesday 11 Aug 2021, 13:10 → 14:30 Europe/London

Access Grid (RAL R89)

ACTIONS (From last meeting):

DM - Add brief current status to GGUS tickets to aid understanding of non-regular attendees - COMPLETE

TBr - Increase the number of WN's  running XrootD 5.2 from 10 to 20 to help facilitate the investigation of low I/O rates. - COMPLETE

ACTIONS (New)

TBr - Liasions have decided that the lower rate of I/O with XrootD 5.2 is acceptabel and have authorised TBr to roll-out to the complete batch farm.

 

13:18 → 13:19 Major Incidents Changes

13:19 → 13:20 Summary of Operational Status and Issues

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

Weekly Report 11 August 2021.docx

Weekly Report 11 August 2021.pdf

13:20 → 13:21 GGUS /RT Tickets

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

13:21 → 13:22 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

13:22 → 13:23 Experiment Operational Issues

13:24 → 13:25 VO-Liaison ATLAS

Speakers: James William Walder (Science and Technology Facilities Council STFC (GB)), Dr Tim Adye (Science and Technology Facilities Council STFC (GB))

RAL batch queues set offline last night (Triggered by CASTOR downtime).

Online briefly, but now set offline for the weekend (48Hr prior to Downtime). 

 - Could it be easily done to have a managed release of jobs when downtime released? e.g. remove surplus options / cap the VOs to their pledge? 

 

External Gateways running with Webdav enabled. Input from ATLAS experts needed before running TPC passive mode tests.

 

13:25 → 13:26 VO Liaison CMS

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

jobsBySecondaryInput_KIT.pdf

jobsBySecondaryInput_KIT.pptx

13:30 → 13:31 VO Liaison LHCb

Speaker: Raja Nandakumar (Science and Technology Facilities Council STFC (GB))

LHCb:

 

1. arc-ce-test02 : LHCbDirac jobs run fine there (tested in the LHCb certification system).

 

2. https://ggus.eu/index.php?mode=ticket_info&ticket_id=151955

Title : Checksums using xrootd on ECHO taking a long time.

Issue : As in title

Status : Open - possibly implemented next week after code review?

 

3. https://ggus.eu/index.php?mode=ticket_info&ticket_id=152009

Title : FTS3 transfers Failed (RAL => CERN) RAL-LCG2

Issue : Data corruption at RAL again. Updated with as much information as available about the file in question.

Note: Similar issue in old ticket https://ggus.eu/index.php?mode=ticket_info&ticket_id=150898

Status : Need to understand why the original write failure occurs - so, it is likely a CEPH / ECHO issue as the error is seen both in gsiftp and xrootd writes. The problem was first seen on 8 March 2021 and not seen before then. So, some maybe related to some change done before then.

 

4. https://ggus.eu/index.php?mode=ticket_info&ticket_id=150653

Title : FTS error: libX509SciTokensIssuer.so ...

Issue : RAL FTS does not support macaroons. FTS upgrade needed at RAL.

Resolution : Upgraded - to be tested by LHCb when Brian gets some information about authentication from FTS developers

Status : Waiting for upgrade to be scheduled.

 

5. https://ggus.eu/index.php?mode=ticket_info&ticket_id=142350

Title : Proble accessing some LHCb files at RAL

Issue : xrootd vector reads from CEPH (ECHO@RAL) not properly implemented.

Status : Waiting for fix.

 

 

DUNE:

 

Looking forward to http(s) access for ECHO (xrootd5)

Waiting for CTA to go into production at RAL for testing tape access.

 

13:35 → 13:38 VO Liaison LSST

Speaker: Joshua Kitenge

13:40 → 13:41 VO Liaison Others

13:45 → 13:46 Experiment Planning

13:50 → 13:51 Euclid

13:55 → 13:56 SKA

14:00 → 14:10 Dune/protoDune

14:10 → 14:11 AOB

14:15 → 14:16 Any other Business

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