Creating incoming access on the same port to two internal addresses

[janp1]

Hi Community,

My problem is that I need to allow incoming traffic on TCP port 8180 to two internal addresses. When I configure port forwarding to one address, no problem. When I create a forwarding rule to the second IP on the same port, I get an error of an overlap. 

How will I be able to allow this?

Thanx

[RaphaelL]

Do you own more than 1 public IP ?

If so , this can be achieve with NATing . Here are some great examples : https://documentation.meraki.com/MX/NAT_and_Port_Forwarding/Port_Forwarding_and_NAT_Rules_on_the_MX

[janp1]

Unfortunately , only 1 public IP.

[RaphaelL]

Are the servers on 8180 running the same application ? A.k.a your goal is to load balance your trafic to both server ?

1.1.1.1:8180 -->  192.168.1.10:8180  or 192.168.1.20:8180  

[janp1]

Hi RaphaelL,

No , not for load-balancing. Different roles/applications. One device is a decoder, and the other a recorder. Both need to have incoming traffic on the same port.

[Brash]

There's really no way you can forward the same port to 2 different destinations, as there's no identifier to know where to send the traffic. If inbound traffic is supposed to be split between the 2 destinations (eg. on a round robin basis), you'll need to put a load balancer in front to redirect traffic accordingly. 
Otherwise, if they are separate applications that just happen to have an overlap, you'll need to move one of the applications to a different port.

[KarstenI]

As already mentioned, you need to use two different ports. But I would also think about the implementation if you really should host your application onsite in this case with only one public IP. Putting both application on the systems of a public ISP or the cloud could be a better approach.