RAL Tier1 Operations Report for 14th February 2018
| Review of Issues during the week 7th February 2018 January 2018 to 14th February 2018
|
- We had an incident with our disk servers that deal with tape recalls/migrations on our Gen instance. A network misconfiguration was introduced after they had been physically move to a new rack location last Thursday. As a result, tape transfers were not running over the weekend, with this issue being resolved on Monday morning. We are holding a post-mortem review on this incident with the view of improving the relevant processes and to ensure we reduce the risk of this problem happening again.
- A high failure rate for both ATLAS and CMS for writes into Echo was reported on Friday. These GridFTP transfer errors were being reported as "Address already in use"
It should be noted that while the GridFTP traffic was not unusually high, ATLAS were running almost 14k jobs on the farm which is significantly higher than normal.
After investigation it was decided that while the ports aren't exhausted the GridFTP server thinks they are, and increasing the allowed range which is currently 2000 ports from 50000 - 52000 to 50000 - 54000.
Further investigation also revealed that GridFTP requires a contiguous set of ports. So, a 10-stream transfer would require 50000-50010 to be free. This would cause ports to run out much quicker than might be expected.
The change to increase port range to 50000-60000 was rolled out on ceph-gw4 and transfers continued without any issue, subsequently this change was rolled out rolled out on all gateways.
| Current operational status and issues
|
- The problems with data flows through the site firewall being restricted is still present. New firewall kit has be purchased and delivered, awaiting deployment.
| Resolved Castor Disk Server Issues
|
| Ongoing Castor Disk Server Issues
|
| Limits on concurrent batch system jobs.
|
- CMS Multicore 550
- ALICE jobs 750. (Attempt to re-balance farm)
| Notable Changes made since the last meeting.
|
- Move to IPv6 connectivity - currently on 10Gbit links - to share the higher bandwidth (40Gbit) links used by IPv4. This has been approved at the CAB meeting (13/2/18), and will implemented on the 21/2/2018.
| Entries in GOC DB starting since the last report.
|
- No downtime scheduled in the GOCDB between 2018-02-07 and 2018-02-14
| Advanced warning for other interventions
|
| The following items are being discussed and are still to be formally scheduled and announced.
|
Listing by category:
- Castor:
- Update systems to use SL7 and configured by Quattor/Aquilon. (Tape servers done)
- Move to generic Castor headnodes.
- Networking
- Extend the number of services on the production network with IPv6 dual stack. (Done for Perfsonar, FTS3, all squids and the CVMFS Stratum-1 servers).
- Replacement (upgrade) of RAL firewall.
- Internal
- DNS servers will be rolled out within the Tier1 network.
- Infrastructure
- Testing of power distribution boards in the R89 machine room is being scheduled for some time late July / Early August. The effect of this on our services is being discussed.
| Open GGUS Tickets (Snapshot during morning of meeting)
|
| Request id
|
Affected vo
|
Status
|
Priority
|
Date of creation
|
Last update
|
Type of problem
|
Subject
|
Scope
|
| 117683
|
none
|
on hold
|
less urgent
|
18/11/2015
|
03/01/2018
|
Information System
|
CASTOR at RAL not publishing GLUE 2
|
EGI
|
| 124876
|
ops
|
on hold
|
less urgent
|
07/11/2016
|
13/11/2017
|
Operations
|
[Rod Dashboard] Issue detected : hr.srce.GridFTP-Transfer-ops@gridftp.echo.stfc.ac.uk
|
EGI
|
| 127597
|
cms
|
on hold
|
urgent
|
07/04/2017
|
29/01/2018
|
File Transfer
|
Check networking and xrootd RAL-CERN performance
|
EGI
|
| 132589
|
lhcb
|
in progress
|
very urgent
|
21/12/2017
|
31/01/2018
|
Local Batch System
|
Killed pilots at RAL
|
WLCG
|
| 133399
|
atlas
|
in progress
|
less urgent
|
09/02/2018
|
12/02/2018
|
File Transfer
|
Transfers to RAL-LCG2-ECHO fail with "Address already in use"
|
WLCG
|
| 133421
|
snoplus.snolab.ca
|
in progress
|
urgent
|
12/02/2018
|
12/02/2018
|
File Transfer
|
Failed Transfers since Friday 10:00
|
EGI
|
| GGUS Tickets Closed Last week
|
| Request id
|
Affected vo
|
Status
|
Priority
|
Date of creation
|
Last update
|
Type of problem
|
Subject
|
Scope
|
| 132802
|
cms
|
closed
|
urgent
|
11/01/2018
|
09/02/2018
|
CMS_AAA WAN Access
|
Low HC xrootd success rates at T1_UK_RAL
|
WLCG
|
| 132935
|
atlas
|
closed
|
less urgent
|
18/01/2018
|
07/02/2018
|
Storage Systems
|
UK RAL-LCG2: deletion errors
|
WLCG
|
| 133092
|
atlas
|
closed
|
top priority
|
29/01/2018
|
12/02/2018
|
Other
|
RAL FTS server in troubles
|
WLCG
|
| 133425
|
ops
|
verified
|
less urgent
|
12/02/2018
|
13/02/2018
|
Operations
|
[Rod Dashboard] Issue detected : org.nordugrid.ARC-CE-sw-csh-ops@arc-ce02.gridpp.rl.ac.uk
|
EGI
|
| Day
|
ALICE
|
ATLAS
|
ATLAS-ECHO
|
CMS
|
LHCb
|
OPS
|
Comment
|
| 2018-02-07
|
100
|
100
|
100
|
100
|
100
|
100
|
|
| 2018-02-08
|
100
|
100
|
100
|
100
|
100
|
100
|
|
| 2018-02-09
|
100
|
100
|
100
|
100
|
100
|
100
|
|
| 2018-02-10
|
91
|
100
|
100
|
100
|
100
|
100
|
|
| 2018-02-11
|
99
|
100
|
100
|
100
|
100
|
100
|
|
| 2018-02-12
|
79
|
98
|
100
|
100
|
100
|
100
|
|
| 2018-02-13
|
100
|
100
|
100
|
100
|
100
|
100
|
|
Key: Atlas HC = Atlas HammerCloud (Queue RAL-LCG2_UCORE, Template 841); CMS HC = CMS HammerCloud
| Day |
Atlas HC |
CMS HC |
Comment
|
| 2018/02/07 |
100 |
100 |
|
| 2018/02/08 |
98 |
100 |
|
| 2018/02/09 |
100 |
100 |
|
| 2018/02/10 |
90 |
100 |
|
| 2018/02/11 |
100 |
100 |
|
| 2018/02/12 |
94 |
100 |
|
| 2018/02/13 |
96 |
100 |
|
- It was noted that one morning this week Echo was delivering data to teh worker nodes at around 15GBytes/sec.
- The MICE experiment is coming to an end. Future acess to MICE data was briefly discussed.
- It was noted that there are plans to connect the RAL network to JANET at 100Gbit.
