Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 12 Dec 1998 01:24:00 -0600
From:      "Singh, Hardeep           IN" <singhh@delpo1.in.unisys.com>
To:        FreeBSD <freebsd-questions@FreeBSD.ORG>
Subject:   Tcpdump strange problem
Message-ID:  <199812111958.TAA18221@eamail1.unisys.com>

next in thread | raw e-mail | index | archive | help
Hello Gentlemen,

I want to run tcpdump on my machine to monitor traffic.
I have done following things so far

1.Recompiling the Kernel with  statement as
pseudo-device bpfilter   4

2.All me devices(and network cards are working extremely fine) and I have
DEC PCI Ethernet DECCHip
adapter with corresponding entry in kernel of de0 and is working fine.

3.I have installed  tcpdump and trafshow on my machine.
Now when i run tcpdump or trafshow the following happens

1.All packets directed to and from my host are  shown
2.All packets for broadcast and multicast are shown e.g arp request and arp
replies
3.When I invoke tcpdump for viewing packets on some host celtics e.g
>tcpdump -n host celtics
 The reply is as >>>>
Dec 11 21:56:11 Myhost /kernel:  de0: promiscuous mode enabled
tcpdump:listening on de0
/**
Only
arp packets for celtics are visible
**/
^C    /* Aborting operation  */

1051 packets  received by filter
0 packets dropped by kernel

4.Other packets from HostA to HostB where both HostA and HostB and proper
hosts are
NOT visible at all despite of choosing (probably as many as possible)
expressions given to tcpdump and trafshow as command line arguments.


Is there some change to be made in code for getting the packets destined for
other hosts to be picked up by my network card.In fact  the no of packets
that appear in the statement that are received by filter
do seem to indicate that the kernel is getting the packets but some how it
the pplication is not printing them.Please help me with it.I had given a try
to FAQ,HelpBook and mail list archive but could not find my answer any where

Hoping for  quick and prompt reply
Thanks and Regards
singhh@delpo1.in.unisys.com
Hardeep Singh








To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-questions" in the body of the message



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199812111958.TAA18221>