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The unreachability (black bars in the 3 days plot) starting around 11:00am on November 29th are clearly visible. The black bar around 2012-08-21, 2012-09-08 and 2012-11-13 were SLAc SLAC PingER monitoring host outages. Looking at the 120 days graphs it is seen that there were increased losses (increase in yellow backbround colors) starting around 2012-09-20 in both cases. More recently (see the 3 days plots) these increased for a while to over 20% (more red background colors).