Hi list, I try to install the following network: /-----------------\ | Firewall 1 | \-----------------/ ___________________| |_________________ | 10.2.6.1 10.2.2.1 | | eth1 | | 10.2.6.11 | /----------\ | | Router 1 | | \----------/ | | 10.2.3.11 | | eth0 | |___________________ _______________| | | eth1 | | eth0 10.2.3.10 | | 10.2.2.10 /-----------------\ | Firewall 2 | \-----------------/ | 10.2.4.10 | eth2 | | eth1 | 10.2.4.12 /--------------\ | FTP Server | \--------------/ - The default route of the firewall 2 is 10.2.2.10. - All server have a Mandrake 8.2 with the kernel 2.4.18-6mdksecure except Firewall 2 which have a kernel 2.4.19-16mdk - All incoming request on device eth1 and eth0 of Firewall 2, port 21 are redirected on 10.2.4.12 - All incoming request on device eth1 of Router 1 are redirected on 10.2.3.10 On router 1 * ftp 10.2.3.10 is OK On firewall 1 * ftp 10.2.2.10 is OK * ftp 10.2.6.11 is wrong: When I sniff eth0 on Firewall2, I see the response of ftp server with 10.2.3.10 source ip whereas my iprules and iproute are [root@xxxxxxxxx root]# ip rule list 0: from all lookup local 32764: from 10.2.2.10 lookup T2 32765: from 10.2.3.10 lookup T1 32766: from all lookup main 32767: from all lookup 253 [root@xxxxxxxxx root]# ip route list table T1 10.2.4.0/24 dev eth2 scope link 10.2.3.0/24 dev eth1 scope link default via 10.2.3.11 dev eth1 [root@xxxxxxxxx root]# ip route list table T2 10.2.2.0/24 dev eth0 scope link default via 10.2.2.1 dev eth0 [root@xxxxxxxxx root]# ip route list 10.2.4.0/24 dev eth2 scope link 10.2.2.0/24 dev eth0 scope link 10.2.3.0/24 dev eth1 scope link 127.0.0.0/8 dev lo scope link default via 10.2.2.1 dev eth0 I know that I can solve the problem by adding a nIP address on the FTP server and connect all incoming request from eth1 to the IP1 and all request from eth0 to IP2 but I don't want to apply this solution: in fact, I will have tree providers and more than one server (http, smtp, ftp...) Do you have any idea ? Thanks in advance ------------------------------CONFIGURATION -------------------------------- Configuration of Firewall 2: [root@xxxxxxxxx root]# ip address show 1: lo: <LOOPBACK,UP> mtu 16436 qdisc noqueue link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 brd 127.255.255.255 scope host lo 2: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 100 link/ether 00:08:c7:ac:54:53 brd ff:ff:ff:ff:ff:ff inet 10.2.2.10/24 brd 10.2.2.255 scope global eth0 3: eth1: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 100 link/ether 00:20:18:29:82:74 brd ff:ff:ff:ff:ff:ff inet 10.2.3.10/24 brd 10.2.3.255 scope global eth1 4: eth2: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 100 link/ether 00:50:ba:0a:24:96 brd ff:ff:ff:ff:ff:ff inet 10.2.4.10/24 brd 10.2.4.255 scope global eth2 [root@xxxxxxxxx root]# ip route list table local broadcast 10.2.4.0 dev eth2 proto kernel scope link src 10.2.4.10 broadcast 10.2.2.0 dev eth0 proto kernel scope link src 10.2.2.10 broadcast 10.2.3.255 dev eth1 proto kernel scope link src 10.2.3.10 broadcast 127.255.255.255 dev lo proto kernel scope link src 127.0.0.1 local 10.2.3.10 dev eth1 proto kernel scope host src 10.2.3.10 broadcast 10.2.4.255 dev eth2 proto kernel scope link src 10.2.4.10 broadcast 10.2.3.0 dev eth1 proto kernel scope link src 10.2.3.10 broadcast 10.2.2.255 dev eth0 proto kernel scope link src 10.2.2.10 local 10.2.4.10 dev eth2 proto kernel scope host src 10.2.4.10 local 10.2.2.10 dev eth0 proto kernel scope host src 10.2.2.10 broadcast 127.0.0.0 dev lo proto kernel scope link src 127.0.0.1 local 127.0.0.1 dev lo proto kernel scope host src 127.0.0.1 local 127.0.0.0/8 dev lo proto kernel scope host src 127.0.0.1 [root@xxxxxxxxx root]# iptables-save # Generated by iptables-save v1.2.6a on Mon Apr 14 13:36:50 2003 *mangle :PREROUTING ACCEPT [1732:137673] :INPUT ACCEPT [1640:123143] :FORWARD ACCEPT [17:1078] :OUTPUT ACCEPT [1460:128080] :POSTROUTING ACCEPT [1483:130598] COMMIT # Completed on Mon Apr 14 13:36:50 2003 # Generated by iptables-save v1.2.6a on Mon Apr 14 13:36:50 2003 *nat :PREROUTING ACCEPT [1845:216404] :POSTROUTING ACCEPT [684:50816] :OUTPUT ACCEPT [656:49208] -A PREROUTING -i eth1 -p tcp -m tcp --dport 21 -j DNAT --to-destination 10.2.4.12 -A PREROUTING -i eth0 -p tcp -m tcp --dport 21 -j DNAT --to-destination 10.2.4.12 COMMIT # Completed on Mon Apr 14 13:36:50 2003 # Generated by iptables-save v1.2.6a on Mon Apr 14 13:36:50 2003 *filter :INPUT ACCEPT [10859:901121] :FORWARD ACCEPT [164:9569] :OUTPUT ACCEPT [9873:931838] COMMIT # Completed on Mon Apr 14 13:36:50 2003 ------------------------------------------------------------------------ Configuration of Router 1 [root@xxxxxxx root]# ip address show 1: lo: <LOOPBACK,UP> mtu 16436 qdisc noqueue link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 brd 127.255.255.255 scope host lo 2: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 100 link/ether 00:60:08:50:3a:4a brd ff:ff:ff:ff:ff:ff inet 10.2.3.11/24 brd 10.2.3.255 scope global eth0 3: eth1: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 100 link/ether 00:80:5f:19:fb:74 brd ff:ff:ff:ff:ff:ff inet 10.2.6.11/24 brd 10.2.6.255 scope global eth1 [root@xxxxxxx root]# iptables-save # Generated by iptables-save v1.2.5 on Mon Apr 14 13:38:45 2003 *nat :PREROUTING ACCEPT [25:2349] :POSTROUTING ACCEPT [336:21034] :OUTPUT ACCEPT [332:20794] -A PREROUTING -i eth1 -j DNAT --to-destination 10.2.3.10 COMMIT # Completed on Mon Apr 14 13:38:45 2003 # Generated by iptables-save v1.2.5 on Mon Apr 14 13:38:45 2003 *filter :INPUT ACCEPT [6011:907410] :FORWARD ACCEPT [16:960] :OUTPUT ACCEPT [5592:438525] COMMIT # Completed on Mon Apr 14 13:38:45 2003