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- The data gap from 08:42-11:43 is that the monitor at SLAC sent for each target sent up to 30 pings at roughly each half hour until it received 10 ping responses. However there were no ping responses (i.e. 100% loss). Thus the NNREN web site was not reachable (could be the host crashed, or the network was no longer forwarding the packets, more likely the former given other information you refer to) and ping reports 100% loss.
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- I agree it is very interesting/curious that the connectivity appeared to continue working for 2.5 hours, and then died. One would need to talk to the net and host admins. There are many possibilities ( e.g. maybe the network continued to work but a UPS on the host ran out of battery power, or the backup generator ran out of fuel, or people deliberately shut down power.
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