Here my case,
Server 1 public IP in 1 box (eth0) -> 203.x.x.55/28 and 57/28 gw 203.x.x.49 private IP (eth1) -> 10.10.8.1
Server 2 private IP in 1 box (eth0) -> 10.10.8.5/24 and 7/24 gw 10.10.8.1
Iptables
-A PREROUTING -d 203.x.x.55 -i eth0 -p tcp -m tcp --dport 80 -j DNAT --to-destination 10.10.8.5:80
-A PREROUTING -d 202.10.39.57 -i eth0 -p tcp -m tcp --dport 80 -j DNAT --to-destination 10.10.8.7:80
-A POSTROUTING -s 10.10.8.5 -j SNAT --to-source 203.x.x.55
-A POSTROUTING -s 10.10.8.7 -j SNAT --to-source 203.x.x.57
then my problem are if from ip private with destination port 9100 will use Ip public 55 and port 9200 will use ip public 57.
-A POSTROUTING -s 10.10.8.5/24 -d 10.10.8.1 -p tcp -m tcp --dport 9100 -j SNAT --to-source 202.x.x.55
-A POSTROUTING -s 10.10.8.0/24 -d 10.10.8.1 -p tcp -m tcp --dport 9200 -j SNAT --to-source 202.x.x.57
Result not success, all detected with ip 57.
Whats wrong with this ? thank for you attention.