Week of 170116

WLCG Operations Call details

• At CERN the meeting room is 513 R-068.

• For remote participation we use the Vidyo system. Instructions can be found here.

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 until 15:20, exceptionally to 15:30.
• The SCOD rota for the next few weeks is at ScodRota
• General information about the WLCG Service can be accessed from the Operations Web
• Whenever a particular topic needs to be discussed at the daily meeting requiring information from site or experiments, it is highly recommended to announce it by email to wlcg-operations@cernSPAMNOTNOSPAMPLEASE.ch to make sure that the relevant parties have the time to collect the required information or invite the right people at the meeting.

Tier-1 downtimes

Experiments may experience problems if two or more of their Tier-1 sites are inaccessible at the same time. Therefore Tier-1 sites should do their best to avoid scheduling a downtime classified as "outage" in a time slot overlapping with an "outage" downtime already declared by another Tier-1 site supporting the same VO(s). The following procedure is recommended:

1. A Tier-1 should check the downtimes calendar to see if another Tier-1 has already an "outage" downtime in the desired time slot.
2. If there is a conflict, another time slot should be chosen.
3. In case stronger constraints cannot allow to choose another time slot, the Tier-1 will point out the existence of the conflict to the SCOD mailing list and at the next WLCG operations call, to discuss it with the representatives of the experiments involved and the other Tier-1.

As an additional precaution, the SCOD will check the downtimes calendar for Tier-1 "outage" downtime conflicts at least once during his/her shift, for the current and the following two weeks; in case a conflict is found, it will be discussed at the next operations call, or offline if at least one relevant experiment or site contact is absent.

Links to Tier-1 downtimes

ALICE	ATLAS	CMS	LHCB
	BNL	FNAL

Monday

Attendance:

• local: Luca (SCOD+Storage), Kate (DB+CMS), Maarten (ALICE), Peter (ATLAS), Andrei (DB), Marian (Networks), Vincent (Security), Andrea M. (MW)
• remote: Stephan (CMS), Stefan (LHCb), Matteo (CNAF), David (FNAL), Vincenzo (EGI), Ulf (NDGF), Onno (NLT1), Victor (JINR), Pepe (PIC), John (RAL), Di (TRIUMF)

Experiments round table:

• ATLAS reports ( raw view) -
  • production
    • stable production level ~ 250k running jobs
    • MCORE merging files with 0 events fails (effect of extreme filtering on HION data)
  • storage
    • ongoing staging test to estimate impact of less data replicas on disks - FZK, IN2P3, BNL
    • some sites with old dCache version have problems releasing deleted files
  • frontier servers
    • even with limited number of overlay transformation jobs frontiers servers sometimes overloaded (today capped at ~ 1000)
    • there are probably other jobs that contribute to load on frontier databases
    • call for new meeting to discuss it more seriously also from software & configuration point of view
  • VOMS legacy x RFC proxy issues
    • event picking interface in Panda was not updated to deal with RFC proxy (fixed)
    • AGIS web API still not compatible with RFC proxies
    • different proxy generated voms-proxy-init on lxplus and within ATLAS+rucio environment (CVMFS)
  • WLCG SAM (Service Availability Monitoring) domains did not work on Sunday morning
    • missing targets for *-lb.cern.ch aliases, INC:1248670
  • ATLAS Sites Jamboree this week (January 18-20).

Andrea M. and Maarten pointed out that the fix for dCache is present from version 2.13.50 and that version 2.13 is supported only for ~half a year more.

• CMS reports ( raw view) -
  • no major issues
  • good, steady progress on Monte Carlo production for Moriond 2017
  • apparent low CPU efficiency due to overfilled slots being excluded
  • slots overfilled at sites due to HT Condor bug (triggered by network saturated node) and MadGraph user job running eight processes in single core slot

• ALICE -
  • NTR

• LHCb reports ( raw view) -
  • Activity
    • Mainly running simulation on grid only resources, HLT off b/c of maintenance
  • Site Issues
    • T0: The LHCb internal name of the T0 batch resources has been renamed from CERN.ch to CERN.cern (to distinguish it from other .ch resources)
    • T1:
      • RAL: file access issue: User can not open files (GGUS:125856), will be followed up after the Wed DT

Sites / Services round table:

• ASGC:
• BNL: ATLAS Staging test from Tape ran fine, site feedback will be given at the ATLAS Jamboree (this week).
• CNAF: NTR
• EGI: NTR
• FNAL: NTR
• GridPP:
• IN2P3:
• JINR:
  • Our farm still underloaded, 40-60 x 10 cores slots are free for the last few weeks. Site is for CMS only, so a large part of our resources is completely idle.
    • Stephan: we are looking into it
  • Local network glitch 09.01.2017 from 12:00 MSK for about 1 hour.
• KISTI:
• KIT:
• NDGF: NTR
• NL-T1:
  • Tomorrow morning SARA has a "warning" network maintenance: one rack currently has a single uplink and we want to make it redundant.
• NRC-KI:
• OSG:
• PIC: NTR
• RAL: Scheduled CASTOR upgrade for LHCb next Wednesday
• TRIUMF: NTR

• CERN computing services:
  • HTCondor upgrade scheduled for next Monday (23rd) OTG:0035096
• CERN storage services: NTR
• CERN databases: NTR
• GGUS: NTR
• Monitoring:
• MW Officer:
  • new ARC-CE release (http://www.nordugrid.org/arc/releases/15.03u11/release_notes_15.03u11.html) available also in EPEL. It fixes an issue with HTCondor 8.5.5 reported by some sites affecting the job status query
• Networks: NTR
• Security: three issues, two of them are now fixed, the investigation for the last one is still ongoing

AOB: