Week of 220725

WLCG Operations Call details

• For remote participation we use Zoom: https://cern.zoom.us/j/99591482961
  • The pass code is provided on the wlcg-operations list.
  • You can contact the wlcg-ops-coord-chairpeople list (at cern.ch) if you do not manage to subscribe.

General Information

• The purpose of the meeting is:
  • to report significant operational issues (i.e. issues which can or did degrade experiment or site operations) which are ongoing or were resolved after the previous meeting;
  • to announce or schedule interventions at Tier-1 sites;
  • to inform about recent or upcoming changes in the experiment activities or systems having a visible impact on sites;
  • to provide important news about the middleware;
  • to communicate any other information considered interesting for WLCG operations.
• The meeting should run from 15:00 Geneva time until 15:20, exceptionally to 15:30.
• The SCOD rota for the next few weeks is at ScodRota
• Whenever a particular topic needs to be discussed at the operations meeting requiring information from sites or experiments, it is highly recommended to announce it by email to the wlcg-scod list (at cern.ch) to allow the SCOD to make sure that the relevant parties have the time to collect the required information, or invite the right people at the meeting.

Best practices for scheduled downtimes

• Best practices for scheduled downtimes

Monday

Attendance:

• remote: Alessandro (CNAF), Andrew (TRIUMF), Borja (Chair, Monitoring), Christoph (CMS), Darren (RAL), David (IN2P3), David (FNAL), Doug (BNL), Julia (WLCG), Marian (Networking), Mark (LHCb), Petr (ATLAS), Pinja (Security), Xavier (KIT)

Experiments round table:

• ATLAS reports ( raw view) -
  • half day connection issues from RAL CTA to CERN (GGUS:158080)
  • small fraction (~ 1%) of very slow exports from T0 (GGUS:157985)
  • CNAF network (GGUS:158067)

• CMS reports ( raw view) -
  • Gitlab authentication issues at CERN (OTG:0072212) let CMS WN SAM test turn to "Warning".

• ALICE
  • NTR

• LHCb reports ( raw view) -
  • Issues:
    • Work ongoing on the issues transferring between PIC and CNAF/INFN (GGUS:157955, GGUS:158004)
      • Asymmetry between the route between CNAF and PIC identified.
      • WLCG Network Throughput team is following up with GARR, CNAF and PIC
    • Signficant transfer problems to RAL on Friday due to CEPH key ring issues (GGUS:158120). Solved in good order.

• • Christoph: Do you actually see errors for the network issues, or it was deduced by observation?
  • Mark: We are seeing some specific errors in given IP addresses when CNAF workers connect
  • Marian: Issue seems to be more no connection over IPv4 between PIC and CNAF, Eduardo is working on this

Sites / Services round table:

• ASGC: NC
• BNL: NTR
• CNAF: NTR
• EGI: NC
• FNAL: NTR
• IN2P3: NTR
• JINR: NTR
• KISTI: NC
• KIT: A brief dip in (power) voltage on Wednesday noon caused problems for several systems, e.g. all jobs in the batch farm crashed. It took us several hours to fix all the fallout from that incident.
• NDGF: NC
• NL-T1: NTR
• NRC-KI: NC
• OSG: NC
• PIC: NC
• RAL: NTR
• TRIUMF: Scheduled outage for Network Maintenance on Friday July 30 00:00 - July 30 02:00 UTC. GOCDB: https://goc.egi.eu/portal/index.php?Page_Type=Downtime&id=32681

• CERN computing services: NC
• CERN storage services: NC
• CERN databases: NC
• GGUS: NTR
• Monitoring: NTR
• Middleware: NTR
• Networks:
  • CNAF is currently unreachable from PIC via IPv4, this is being followed up by GARR/CERN network experts
  • ESNet equipment installation was postponed to August/September (specific date is not available yet) - OTG:0071903, OTG:0071902
• Security: NTR

AOB: