>> 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 192.168.0.2 will be >> changed to that of ppp0 , for example say 10.10.10.1 No, it does not say "changed to that of ppp0" but: _change_all_packets_that_go_out_of_ppp0_ (...to the address belonging to ppp0) >> Now my question is, when the reply comes, their destination addr will be >> that of ppp0 i.e 10.10.10.1 >> Who will reverse translate this 10.10.10.1 destination addr to actual >> 192.168.0.2 ? >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 --
