I have a Linux router like:
İnternet <-> Linux <-> DMZ
We have /25 subnet of 128 IP addresses. Those are NATed into servers in DMZ. If I did not configure all of these IP addresses as IP aliases in external interface of Linux, those IPs did not work.
Lets example, 188.8.131.52 IP is not defined in Linux. I see packets targeted to 184.108.40.206 at external interface of Linux with tcpdump. However, NAT rules does not work. If I define 220.127.116.11 as eth1:1 at external interface, NAT rules start to work.
Kernel is 2.6.18 latest Centos 5.5 kernel.
I need your kind comments.