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Network Issues after UltraLight? Router at Starlight (R04CHI?) was Retired

On August 28 around noon Eastern the UltraLight? router was retired at Starlight. This resulted in the loss of around 1100 routes that AGLT2 was receiving and only about 250 additional routes came in via the USLHCnet E600 connection for AGLT2. The primary impacts from this change:
  • We lost routing to some subnets at BNL, one of which ( hosted the pilot factory AGLT2 needed access to
  • Three ultralight.org subnets lost routing
    • VLAN 57 hosting 192.84.86.126/28 (Terapaths/VNODs/ESCPS/StorNet nodes)
    • VLAN 2002 hosting 198.32.43.32/28 (REDDnet nodes)
    • VLAN 2001 hosting 198.32.43.48/28 (REDDnet nodes)
  • Various R&E subnets relevant to LHC started to have problems contacting our SRM headnode head01.aglt2.org
    • http://atlas.web.cern.ch/Atlas/GROUPS/DATABASE/project/ddm/releases/TiersOfATLASCache.py By searching it you can find the locations below (note these seem to have a problem reaching head01.aglt2.org). Below are the locations we have seen problems with. All of these fail to contact head01.aglt2.org
    • LIP-LISBON_DATADISK srm01.lip.pt 193.136.90.58
      • Have Route for this
      • Traceroute is good, so most likely an end site issue.
    • NCG-INGRID-PT_DATADISK srm01.ncg.ingrid.pt 193.136.75.141
      • Have Route for this
      • Traceroute is good, so most likely an end site issue.
    • LIP-COIMBRA_DATADISK storm.gridc.lip.pt 193.137.227.11
      • Have Route for this
      • Traceroute is good, so most likely an end site issue.
    • UAM-LCG2_DATADISK grid002.ft.uam.es 150.244.244.41
    • IFIC-LCG2_DATADISK srmv2.ific.uv.es 147.156.116.232
      • Have route for this
      • Traceroute is good, so most likely an end site issue.
    • IFAE_DATADISK srmifae.pic.es 193.109.172.158
      • Do not have route for this Network, need to figure this one out
    • SARA-MATRIX_DATADISK srm.grid.sara.nl 145.100.32.248
      • Have Route for this
      • Traceroute is good, so most likely an end site issue.
The first main bullet was addressed by getting ESnet to remove the filter on the AGLT2 subnets that USLHCnet was sending them. (Fixed around noon Eastern on August 29, 2012)

The second main bullet (Ultralight.org subnets) was also fixed by ESnet accepting the routes (as above)

The third main bullet is still a problem. We need to figure out why those remote hosts can't get to head01.aglt2.org. Are we missing routes to them?

Longer term, some improvements could be made.
  1. I think it would be beneficial to have AGLT2 and BNL exchange a more complete set of prefixes (certainly including any subnets that host ATLAS or LHC services).
  2. There is still a problem with how traffic is getting to the MSU site. In many cases it comes via UM. We need to make sure MSU can directly receive relevant traffic, rather than having it route via UM.
Others? Let me know.

Shawn -- ShawnMcKee - 29 Aug 2012
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Topic revision: r2 - 30 Aug 2012 - 16:49:58 - RoyHockett
 

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