Using their own looking glass (lg.level3.net) produces all sorts
of route failures as well.
Show Level 3 (Raleigh, NC) Traceroute to so-3-3-0.edge1.SanJose1.Level3.net
(4.68.127.29)
1 ge-7-0-0.mpls1.Raleigh1.Level3.net (209.244.22.33) 0 msec 0 msec 0 msec
2 so-5-1-0.bbr1.Atlanta1.Level3.net (209.247.11.18) 8 msec 8 msec 8 msec
3 * *
ge-10-0.hsa1.Atlanta1.Level3.net (64.159.1.246) !unreachable