Jan Engelhardt jengelh at
Thu Jul 21 13:54:03 CEST 2005

>> Suppose I masquerade ppp0 using
>> iptables -t nat -A POSTROUTING -o ppp0 -j MASQUERADE
>> And now all packets will have a src ip addr as will be
>> changed to that of ppp0 , for example say

No, it does not say "changed to that of ppp0" but:
_change_all_packets_that_go_out_of_ppp0_ ( the address belonging to ppp0)

>> Now my question is, when the reply comes, their destination addr will be
>> that of ppp0 i.e
>> Who will reverse translate this destination addr to actual
>> ?

>This is the job of connection tracking, basically ipt_conntrack.

Nitpick: ip_conntrack.
ipt_conntrack is the module for the -m conntrack match used by iptables.

Jan Engelhardt

More information about the netfilter mailing list