OT: nieprawidlowy ruch pakietow

[Tomasz Buziak [uho]]

Na kompie AAA sa dwa interfejsy eth0 i eth2 przez ktore prowadzona jest
komunikacja z dwiema podsieciami 192.168.1.0/24 i 192.168.2.0/24.

Pingujac z kompa AAA do kompa BBB bedacego w podsieci 192.168.2.0/24 jest
wszystko w pozadku

[root w AAA etc]# ping -I eth2 192.168.2.61
PING 192.168.2.61 (192.168.2.61) from 192.168.2.64 eth2: 56(84) bytes of data.
64 bytes from 192.168.2.61: icmp_seq=1 ttl=64 time=0.697 ms
64 bytes from 192.168.2.61: icmp_seq=2 ttl=64 time=0.615 ms
--- 192.168.2.61 ping statistics ---
2 packets transmitted, 2 received, 0% loss, time 1011ms
rtt min/avg/max/mdev = 0.615/0.656/0.697/0.041 ms

ale na kompie AAA badajac ruch pakietow tcpdumpem dostaje taki wynik:

[root w AAA root]# tcpdump -i eth0 ip host 192.168.2.61
tcpdump: listening on eth0
08:04:41.615353 192.168.2.61 > 192.168.2.64: icmp: echo reply
08:04:42.621518 192.168.2.61 > 192.168.2.64: icmp: echo reply

2 packets received by filter
0 packets dropped by kernel

[root w AAA root]# tcpdump -i eth2 ip host 192.168.2.61
tcpdump: listening on eth2
08:04:47.661026 192.168.2.64 > 192.168.2.61: icmp: echo request (DF)
08:04:48.671093 192.168.2.64 > 192.168.2.61: icmp: echo request (DF)

2 packets received by filter
0 packets dropped by kernel

dlaczego komp AAA wysyla prozbe przez eth2 a dostaje odpowiedz przez eth0, gdy
na kompie AAA routing jest taki:
[root w AAA etc]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
80.53.11.148    0.0.0.0         255.255.255.252 U     0      0        0 eth1
192.168.2.0     0.0.0.0         255.255.255.0   U     0      0        0 eth2
192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
0.0.0.0         80.53.11.149    0.0.0.0         UG    0      0        0 eth1

a na kompie BBB, taki:

[root w BBB root]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.3.0     0.0.0.0         255.255.255.0   U     0      0        0 eth2
192.168.2.0     0.0.0.0         255.255.255.0   U     0      0        0 eth1
192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
127.0.0.0       0.0.0.0         255.0.0.0       U     0      0        0 lo
0.0.0.0         192.168.2.64    0.0.0.0         UG    0      0        0 eth1

???

co mozna z tym zrobic zeby pakiety wychodzace danym interfejsem wracaly tym
samym? ten problem utrudnia mi budowe firewalla

--
Tomasz Buziak, pozdrawiam ...
# cd /pub && more beer