подсчет трафика с помощью iptables.....

Из документации по iptables:
Table 1. Forwarded packets
Step Table Chain Comment
1
On the wire(ie, internet)
2
Comes in on the interface(ie, eth0)
3
mangle PREROUTING
This chain is normally used for mangling packets, ie, changing TOS and so on.
4
nat PREROUTING
This chain is used for Destination Network Address Translation mainly. Source Network Address Translation is done further on. Avoid filtering in this chain since it will be passed through in certain cases.
5
Routing decision, ie, is the packet destined for our localhost or to be forwarded and where.
6
filter FORWARD
The packet got routed onto the FORWARD chain, only forwarded packets go through here, we do all the filtering here. Note that all traffic that's forwarded goes through here (not only in one direction), so you need to think about it when writing your ruleset.
7
nat POSTROUTING
This chain should first and foremost be used for Source Network Address Translation, avoid doing filtering here since certain packets might pass this chain without ever hitting it. This is also where Masquerading is done.
8
Goes out on the outgoing interface (ie, eth1).
9
Out on the wire again (ie, LAN).
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Отсюда вроде как следует, что при прохождении пакетов через
тачку, последняя таблица для них будет nat и правило POSTROUTING.
Однако не срастается....
Вообще же нужно следующее:
Есть маршрутизации и NAT - нужно подсчитать трафик входящий в карточку
и выходящий из нее. Чтобы это все потом например в mrtg нарисовать
можно было.
Как сделать?