RAL Tier1 Operations Report for 9th March 2016
| Review of Issues during the week 2nd to 9th March 2016.
|
- There was a problem of packet loss within part of the Tier1 network. These did not seem to affect operations. For example there was no packet loss between disk servers and worker nodes, but there was when accessing the worker nodes from staff desktop systems. The problem was first noticed on Tuesday of last week (1st March). It was finally resolved on Tuesday (8th March) having been traced to a component in OpenStack which is being used to develop new cloud infrastructure.
| Resolved Disk Server Issues
|
| Current operational status and issues
|
- There is a problem seen by LHCb of a low but persistent rate of failure when copying the results of batch jobs to Castor. There is also a further problem that sometimes occurs when these (failed) writes are attempted to storage at other sites. A recent modification has improved, but not completed fixed this.
- The intermittent, low-level, load-related packet loss seen over external connections is still being tracked. Likewise we have been working to understand some remaining low level of packet loss seen within a part of our Tier1 network.
| Ongoing Disk Server Issues
|
- GDSS677 (CMSTape - D0T1) crashed in the morning of Tuesday 8th March. It is being checked out.
| Notable Changes made since the last meeting.
|
| Advanced warning for other interventions
|
| The following items are being discussed and are still to be formally scheduled and announced.
|
- At Risk on the whole Tier1 next Monday, 14th March, 11:00 - 16:00 while a network reconfiguration is made followed by the firmware update in a pair of network switches. (Note: The date of this work was updated after the meeting.)
- The Castor 2.1.15 update is pending. Testing has shown a database related performance issue which is being followed up. We await successful resolution of that problem and completion of testing before scheduling.
- Decommissioning of "GEN Scratch" storage in Castor.
Listing by category:
- Databases:
- Switch LFC/3D to new Database Infrastructure.
- Castor:
- Update SRMs to new version (includes updating to SL6).
- Update to Castor version 2.1.15.
- Migration of data from T10KC to T10KD tapes (affects Atlas & LHCb data).
- Networking:
- Replace the UKLight Router. Then upgrade the 'bypass' link to the RAL border routers to 2*10Gbit.
- Fabric
- Firmware updates on remaining EMC disk arrays (Castor, LFC)
- Grid Services
- A Load Balancer (HAProxy) will be used in front of the FTS service.
| Entries in GOC DB starting since the last report.
|
| Service
|
Scheduled?
|
Outage/At Risk
|
Start
|
End
|
Duration
|
Reason
|
| lcgfts3.gridpp.rl.ac.uk,
|
SCHEDULED
|
WARNING
|
03/03/2016 10:00
|
03/03/2016 11:00
|
1 hour
|
Update of Production FTS3 service to version 3.4.2
|
| Open GGUS Tickets (Snapshot during morning of meeting)
|
| GGUS ID |
Level |
Urgency |
State |
Creation |
Last Update |
VO |
Subject
|
| 119841
|
Amber
|
Less Urgent
|
In Progress
|
2016-03-01
|
2016-03-08
|
LHCb
|
HTTP support for lcgcadm04.gridpp.rl.ac.uk
|
| 117683
|
Green
|
Less Urgent
|
In Progress
|
2015-11-18
|
2016-02-17
|
|
CASTOR at RAL not publishing GLUE 2
|
Key: Atlas HC = Atlas HammerCloud (Queue ANALY_RAL_SL6, Template 508); CMS HC = CMS HammerCloud
| Day |
OPS |
Alice |
Atlas |
CMS |
LHCb |
Atlas HC |
CMS HC |
Comment
|
| 02/03/16 |
100 |
100 |
90 |
60 |
100 |
100 |
100 |
Problem affected CE tests across many sites for both Atlas & CMS.
|
| 03/03/16 |
100 |
100 |
100 |
61 |
100 |
100 |
100 |
Ongoing problem affecting CE tests across many sites for CMS.
|
| 04/03/16 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
|
| 05/03/16 |
100 |
100 |
100 |
100 |
100 |
100 |
N/A |
|
| 06/03/16 |
100 |
100 |
87 |
100 |
100 |
100 |
N/A |
No results for Atlas tests - not sure what is happening.
|
| 07/03/16 |
100 |
100 |
56 |
66 |
73 |
100 |
100 |
Missing monitoring results. To be fixed up.
|
| 08/03/16 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
|
