There are some interesting results from the Japanese earthquake of March 11th 2011. According to http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/usc0001xgp.phpl the big (8.9) one was Friday, March 11, 2011 at 05:46:23 UTC.
PingER results
None All of the 6 hosts that PingER monitors in Japan went down for an extended period of time at stayed up at the time of the earthquake. The hosts monitored are seen in the table below.
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