On Monday 01 July 2002 12:20 am, angela  cearns wrote:

> hello group,
>    i want to check if there is anyway  i can measure the # of
> packets after the iptables acted on them i.e. after dropping the
> packets. i use ethereal, it gives me all the packets before the
> iptables have acted on?

What do you mean by "the number of packets after iptables dropped the 
packets" ?

I assume you don't mean the packets which got dropped, and I assume you don't 
mean the further packets in the communication stream which never even arrive, 
because the earlier ones got dropped, so which packets are you trying to 
capture / count ?

Does it help to remind you that almost all packets dropped by netfilter rules 
are SYN packets (ie the first part of the TCP three-way handshake) and the 
very purpose of dropping them is so that the 3-way handshake does not 
complete, and the session does not start transmitting data ?

Give us an example of a TCP or UDP session with a drop rule, and tell us 
which packets you want to count, and we'll have a think.....

 

Antony.

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