[Snort-users] a lot of Loopback traffic being logged.

Milan Kocián milon at ...11701...
Sun Apr 25 11:28:03 EDT 2004


On Fri, 2004-04-23 at 19:23, Chuck Holley wrote:
> Did you sniff for 127.0.0.1 packets?  Im using tcpdump and I sniffed for a
> while with this command:  tcpdump src 127.0.0.1 -s 1518 -i eth0 -w dump
> 
> Im assuming im doing this right.  Im trying to log only packets form
> 127.0.0.1 and log the whole Ethernet packet 1518 on interface eth0 and write
> to a file called dump.
> 
> Now, I did this and got two loggings in tcpdump:
> 
> 13:04:11.172652 IP hal2.http > 192.168.42.50.1361: R 0:0(0) ack 799408129
> win 0
> 13:04:54.391786 IP hal2.http > 192.168.42.52.1196: R 0:0(0) ack 1316880385
> win 0
> 
> hal2 is the server that has tcpdump on it. Is this machine one of the boxes
> that is sending out the 127.0.0.1, or did I simply pickup two packets sent
> out form hal2 to these other machines. 
> 
> I looked at snort and the exact same ip's, with the exact same ports were
> logged coming from 127.0.0.1
> 
> To say the least im confused even more!!
> 
> 

Hi,
 I see it on my external interface too. I used tcpdump with -e parameter
to display MAC address of the sender.

tcpdump -e -i eth1 src host 127.0.0.1

I find that MAC address of loopback packets is my ISP's Cisco switch.

So all packets come from external network (I think). I am connected over
wi-fi AP and when I sniffed, I have seen that these packets coming to
most connected people in this AP.

I don't know what it can be.

Regards,

Milan Kocian





More information about the Snort-users mailing list