CERN Home   IT Home   Sitemap   Phonebook   Need Help?
IT Home Important Disruptive Network Intervention on March 19th

IT Division
Local Site
IT Services
Access to Facilities
Desktops & Portables
Physics Computing
Technical Computing
Index of Services
Other Services
Divisional Information
What We Do
Divisional Structure
Divisional Administration
Minutes & Reports
Safety in IT Division
Job Opportunities
More on Computing
CERN School of Computing


Important Disruptive Network Intervention on

March 19th 

*** New Final Date ***

Update on 19 March 17:50:

From: IT FIO
Sent: 19 March 2009 17:50

Subject: CERN tier-0 services back


All CERN tier-0 physics services are now back after the network intervention.

IT/FIO Service Managers


Update on 19 March 11:40 am:

Fom IT CS:

The upgrade of the network equipment (GPN and LCG) is finished

There are some minor issues remaining in the GPN that will be addressed at a later point in time.


Update on 19 March 8:20 am:

From: IT CS

Subject: Upgrade of the GPN is finished.


The upgrade of the switches and routers in the GPN is finished...
One switch has to be replaced (IP10).

The LCG network upgraded started at 8:00 am





An important network maintenance that affects site wide services has been scheduled for Thursday March 19.


This is a new and final date for this intervention.

See: Network maintenance in the computer centre

This maintenance will affect all services that depend on the CERN General Public Network (GPN)

First part

The network equipment in the Computer Center (bldg. 513 and 613) will be upgraded to the latest software version.

During the reboot of the network equipment there will be an interruption of the network.

The intervention will start with the upgrade of the routers of the General Purpose Network which will happen at 06:00 a.m.

This will entail a ~15min interruption, which will affect access to AFS, NICE, MAIL and all Databases which are hosted in the GPN among other services.

Next, the switches in the General Purpose Network that have not been previously upgraded will be upgraded resulting to a ~10min interruption.

All services requiring access to services hosted in the Computer Center will see interruptions.

By 08:00 a.m. the equipment in the General Purpose Network will have been upgraded and this will end the first part of the intervention.

Second Part:

The routers of the LCG network will be upgraded at 08:00 a.m., mainly affecting the Batch system and CASTOR services, including Grid related services.The switches in the LCG network that have not been previously upgraded will be upgraded next.

This network intervention is planned to have finished by noon (12:00 pm) .

IT/CS strongly encourages service managers to enable an early upgrade of the switches their services are connected to, by getting in touch by email or phone.


Should you need more details on this intervention, please contact:

phone: Andreas Hirstius on 74503 or

email: or

phone: Netops on 74927 or




Additional interventions taking advantage of the above interruptions  


IT/FIO will take advantage of the IT/CS announced intervention to perform maintenance tasks to CC hardware during the same period.

Service Managers who wish to schedule an intervention should announce it on this TWiki page:

The detailed schedule, ie order of interventions etc will be finalized when all additional interventions have been announced.

The upgrade of the network equipment has priority. This will be taken into account when scheduling additional interventions.


IT/CS Group

Feedback:IT Webmaster      
Last update:
Thursday, 19-Mar-2009 18:13
Copyright CERN IT Division Homepage