Loss of connectivity from SLAC to multiple sites for about ten hoursLes Cottrell. Page created: September 2, 2004.
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We cannot connect from SLAC to the CERN www.vrvs.org
telnet www.vrvs.org 80indicated that the web port was responding. Also www.vrvs.org responded to a web browser.
Looking at the pings to CERN that are made each 10 minute interval for this period there was no break in connectivity. On the other hand pings from SLAC to Caltech failed from about 15 mins past midnight to a bit before 8:57am.
Looking at the traceroutes from SLAC to IEPM-BW sites SLAC's connectivity to several sites (mainly .edu, but not all .edu) were interrupted during that time. After recovering many of the sites had different routes than before the outage.
Looking at the CENIC maintenance page there was a scheduled outage from midnight to 5:00am. We contacted the CENIC NOC at about 11:15am and they said things were restored about 10:30am.
Looking at the topology of the routes to sites that lost connectivity it was apparent that the common factor wass CENIC.