[Planetlab-users] question on tcpdump on new system

[Ning Qu]

Hi, I have problems receiving packets using raw socket recently (after
system upgrade). The packets are sent back based on tcpdump on the
sender site, but no packets captured on planetlab's tcpdump. For
example, I am pinging one plnode from my own machine, and I do see the
reply:

64 bytes from planetlab-9.CS.Princeton.EDU (128.112.139.108):
icmp_seq=1 ttl=53 time=32.1 ms
64 bytes from planetlab-9.CS.Princeton.EDU (128.112.139.108):
icmp_seq=2 ttl=53 time=32.6 ms


but on planetlab node I received nothing from tcpdump:

@planetlab-9 ~]$ sudo /usr/sbin/tcpdump
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes

0 packets captured
0 packets received by filter
0 packets dropped by kernel

Can anyone help me on that?
thanks