Hi !

I have 4 public ip number with one ISP and want to create 4 gateway that maps to each external ip number..

192.168.5.10 213.115.25.105
192.168.5.11 213.115.25.106
192.168.5.12 213.115.25.107
192.168.5.13 213.115.25.108

The reason for this is that i have mail servers on these ip number, and they using the same port numbers, so i have to use different ip addresses...
i know i can use source Nat to make an internal IP rout out to a specific WAN, but i think this would be better, a little set and forget solution
If i later want to change some client computer to go out by a different external IP, i just have to change the gateway in the DHCP server to make all client move out by a different IP

So I only using PORT1 on my Mikrotik as WAN (Fiber connection) and all my external IP number are on this port, and PORT2 connected to my switch with all my internal ip (192.168.5.10-13.

Is this possible? I never seen a setup like this?

Regards Christer / Sweden

Sounds like you read the manual regarding source nat. If you had read a little more, you would have seen the section on destination nat and 1:1 nat.

So, you use src-nat for the outgoing traffic, dst-nat for incoming traffic. If you use both src-nat and dst-nat together, you'll have a 1:1 mapping that will allow your 4 servers to all use the same ports on different external IP addresses.

Good luck!

Hi !

I Have tested that, but only with one gateway, is t possible to do that with 2 or more gateway ? i know a can source NAT a interna IP to a externa IP
but is it possible to Source NAT a gateway, do redirect all trafic from one gateway to a specific externa IP ?

Regards Christer / Sweden

Yes, you can have multiple gateways. Check out the wiki article on Policy Based Routing. I use this to properly route traffic for customers on an open-access network belonging to multiple providers.

I would probably need to see a detailed description or a diagram showing the desired traffic flow to provide a specific example.

-Troy