RAL Tier1 Operations Report for 12th April2017
| Review of Issues during the week 5th to 12th April 2017.
|
- Problems with the LHCb Castor instance have continued this last week. Under sustained load the service (the SRMs) fail. We are working with LHCb on the problem and are currently running with a reduced job rate of the LHCb merging jobs with are a particular cause of load on Castor. I note that a GGUS alarm ticket was received from LHCb about this problem. Note added just after meeting. As agreed we will revert the SRM update that was made on 23rd March.
- We have also seen problems with the Atlas Castor instance (see availability report below). This Castor instance is running the same Castor SRM version as LHCb.
- On Saturday 8th April there was a problem with one of the Windows Hyper-V 2012 hyperviors. A small number of machines were left in a bad state. This included one of the CEs and an argus system. This affected batch jobs submission during the day. The problem was resolved by the oncall team. We received a GGUS Alarm ticket from LHCb about this problem. There is also an ongoing problem on the Alice VO box that may be related.
- There was a problem with the CMS Castor instance that arose on Saturday. This was caused, at least in part, by the a memory leak in the Castor Transfer Manager. This problem was missed in the noise caused by the above hypervisor problem and was not resolved until Monday morning.
- A transceiver was replaced in one of the four links between the Tier1 network and the OPNR router. Errors were seen in the network monitoring for this specific physical link.
| Resolved Disk Server Issues
|
| Current operational status and issues
|
- We are still seeing a rate of failures of the CMS SAM tests against the SRM. These are affecting our (CMS) availabilities but the level of failures is reduced as compared to a few weeks ago.
| Ongoing Disk Server Issues
|
- gdss673 (LHCb-Tape) was removed from production last Wednesday (5th April) due to it having a double disk failure. Fixing this is ongoing.
| Limits on concurrent batch system jobs.
|
- Atlas Pilot (Analysis) 1500
- CMS Multicore 550
- LHCb 500 (In response to ongoing problems with LHCb Castor.)
| Notable Changes made since the last meeting.
|
- Increased limit on number of CMS multicore jobs from 460 to 550 due to increased pledge for 2017.
- Out of Hours cover for the CEPH ECHO service is being piloted.
| Service
|
Scheduled?
|
Outage/At Risk
|
Start
|
End
|
Duration
|
Reason
|
| lcgwms04.gridpp.rl.ac.uk
|
SCHEDULED
|
OUTAGE
|
12/04/2017 09:05
|
18/04/2017 12:00
|
6 days, 2 hours and 55 minutes
|
server migration
|
| Advanced warning for other interventions
|
| The following items are being discussed and are still to be formally scheduled and announced.
|
Pending - but not yet formally announced:
- Update Castor SRMs - CMS & GEN still to do. This is awaiting a full understanding of the problem seen with LHCb.
- Chiller replacement - work ongoing. (First chiller replacement completed, second in place).
- Merge AtlasScratchDisk into larger Atlas disk pool.
Listing by category:
- Castor:
- Update SRMs to new version, including updating to SL6.
- Bring some newer disk servers ('14 generation) into service, replacing some older ('12 generation) servers.
- Networking
- Enable first services on production network with IPv6 once addressing scheme agreed.
- Infrastructure:
- Two of the chillers supplying the air-conditioning for the R89 machine room are being replaced.
| Entries in GOC DB starting since the last report.
|
| Service
|
Scheduled?
|
Outage/At Risk
|
Start
|
End
|
Duration
|
Reason
|
| lcgwms04.gridpp.rl.ac.uk
|
SCHEDULED
|
OUTAGE
|
12/04/2017 09:05
|
18/04/2017 12:00
|
6 days, 2 hours and 55 minutes
|
server migration
|
| srm-lhcb.gridpp.rl.ac.uk
|
UNSCHEDULED
|
OUTAGE
|
09/04/2017 12:00
|
10/04/2017 12:00
|
24 hours
|
Problems with LHCb transfers
|
| Open GGUS Tickets (Snapshot during morning of meeting)
|
| GGUS ID |
Level |
Urgency |
State |
Creation |
Last Update |
VO |
Subject
|
| 127617
|
Green
|
Alarm
|
In Progress
|
2017-04-09
|
2017-04-09
|
LHCb
|
RAL srm-s are down for LHCb
|
| 127612
|
Green
|
Alarm
|
In Progress
|
2017-04-08
|
2017-04-10
|
LHCb
|
CEs at RAL not responding
|
| 127611
|
Green
|
Top Priority
|
In Progress
|
2017-04-08
|
2017-04-11
|
Alice
|
ALICE VOBOX network problem
|
| 127598
|
Green
|
Urgent
|
In Progress
|
2017-04-07
|
2017-04-07
|
CMS
|
UK XRootD Redirector
|
| 127597
|
Green
|
Urgent
|
In Progress
|
2017-04-07
|
2017-04-10
|
CMS
|
Check networking and xrootd RAL-CERN performance
|
| 127388
|
Green
|
Less urgent
|
In Progress
|
2017-03-29
|
2017-04-03
|
LHCb
|
[FATAL] Connection error for some file
|
| 127240
|
Green
|
Urgent
|
In Progress
|
2017-03-21
|
2017-04-05
|
CMS
|
Staging Test at UK_RAL for Run2
|
| 126905
|
Green
|
Less Urgent
|
Waiting Reply
|
2017-03-02
|
2017-04-03
|
solid
|
finish commissioning cvmfs server for solidexperiment.org
|
| 126184
|
Amber
|
Less Urgent
|
In Progress
|
2017-01-26
|
2017-02-07
|
Atlas
|
Request of inputs for new sites monitoring
|
| 124876
|
Red
|
Less Urgent
|
On Hold
|
2016-11-07
|
2017-01-01
|
OPS
|
[Rod Dashboard] Issue detected : hr.srce.GridFTP-Transfer-ops@gridftp.echo.stfc.ac.uk
|
| 117683
|
Red
|
Less Urgent
|
On Hold
|
2015-11-18
|
2017-03-02
|
|
CASTOR at RAL not publishing GLUE 2.
|
Key: Atlas HC = Atlas HammerCloud (Queue ANALY_RAL_SL6, Template 845); Atlas HC ECHO = Atlas ECHO (Template 841);CMS HC = CMS HammerCloud
| Day |
OPS |
Alice |
Atlas |
CMS |
LHCb |
Atlas HC |
Atlas HC ECHO |
CMS HC |
Comment
|
| 05/04/17 |
100 |
100 |
100 |
100 |
88 |
100 |
100 |
N/A |
SRM Test failures.
|
| 06/04/17 |
100 |
100 |
100 |
99 |
84 |
100 |
100 |
100 |
SRM test failures for both CMS and LHCb.
|
| 07/04/17 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
|
| 08/04/17 |
100 |
96 |
88 |
75 |
94 |
100 |
100 |
100 |
A hypervisor failure led to problems for one of the CEs and argus.
|
| 09/04/17 |
100 |
100 |
100 |
45 |
88 |
100 |
100 |
100 |
CMS: Problem with CMS Castor (transfer manager problems); LHCb - SRM test failures.
|
| 10/04/17 |
100 |
100 |
100 |
60 |
100 |
100 |
99 |
99 |
CMS: Ongoing problem with CMS Castor (above) fixed during morning.
|
| 11/04/17 |
100 |
100 |
58 |
93 |
80 |
98 |
98 |
99 |
All three are SRM test failures caused by Castor problems.
|
