Sooo, part of my job is to program a lot hardware that all come with the same default IP. I want to speed it up the process by doing something like this:
Eth1
10.0.0.100 → 192.168.1.5
10.0.0.101 → 10.100.100.1
Eth2
10.0.0.102 → 192.168.1.5
10.0.0.103 → 10.100.100.1
Eth3
10.0.0.104 → 192.168.1.5
10.0.0.105 → 10.100.100.1
and so on, thus allowing me to program many pieces at the same time.
So far I’ve tried:
- creating a bridge “B1” with an ip of 1.1.1.1
dst-nat 10.0.0.100 (sometimes netmap) to 192.168.1.20
mangle 10.0.0.100 and adding a route-mark “toB1”
add routing path to 10.0.0.100 with pref. source of 1.1.1.1 with route-mark “toB1”
and a ton of variations on that theme. I can get 10.0.0.100 to map to 192.168.1.5 once, but it doesn’t work as soon as I add another 192.168.1.5 device. 
Any suggestions?
EDIT: Added Eth names