Messages in this thread | | | Subject | Re: tcpdump & bad tcp checksum | From | Jes Degn Soerensen <> | Date | 24 Jul 1997 11:24:10 +0200 |
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>>>>> "Eric" == Eric Schenk <Eric.Schenk@dna.lth.se> writes:
Eric> "SethMeister G." <shaggy@jade.cs.binghamton.edu> writes: >> Hi guys, >> >> Just wanted to know why, if the kernel says that there was a packet >> with an invalid tcp checksum, that when I do a tcpdump and grab all >> the tcp segments, tcpdump does not say that an invalid checksum was >> found (and yes, I am using -v)...
Eric> tcpdump only grabs the first few bytes of a packet (by default).
Ehhhmmm, tcpdump for Linux tend to grab the full packet rather than just the header, just checked libpcap-0.4a1 and its still like that. Yup this is bad, especially for `large' MTU networks such as FDDI, and I guess we should do something about this at some point.
Jes
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