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290cottrell@flora04:~>ping -s www.cern.ch
PING www.cern.ch: 56 data bytes
64 bytes from webrlb02.cern.ch (188.184.9.235): icmp_seq=0. time=166. ms
64 bytes from webrlb02.cern.ch (188.184.9.235): icmp_seq=0. time=308. ms
64 bytes from webrlb02.cern.ch (188.184.9.235): icmp_seq=0. time=308. ms
64 bytes from webrlb02.cern.ch (188.184.9.235): icmp_seq=1. time=166. ms
64 bytes from webrlb02.cern.ch (188.184.9.235): icmp_seq=1. time=166. ms
64 bytes from webrlb02.cern.ch (188.184.9.235): icmp_seq=1. time=166. ms
More examples of duplicate pings
Duplicate packets should never occur when pinging a unicast address, and seem to be caused by inappropriate link-level retransmissions. Duplicates may occur in many situations and are rarely (if ever) a good sign, although the presence of low levels of duplicates may not always be cause for alarm. Duplicates are expected when pinging a broadcast or multicast address, since they are not really duplicates but replies from different hosts to the same request. From http://www.gsp.com/cgi-bin/man.cgi?section=8&topic=ping#4
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