Dear all,

I have searched forum before posting this and I have found similar thing but there were nothing to explain how to do next thing:

I have 3 subnets in my mikrotik router and one ISP able to give 3 public addresses via single interface. For ISP I am using one of 3 ethernet ports.
Subnets are 192.168.1.0/24 for wifi
10.100.0.0/24 one group of PCs
10.10.0.0/24 second group of PCs

What I need is to separate public IPs for all 3 subnets. Wifi should go to one and those two subnets to other two. How to do this if public IPs are all in the same interface?

Best Regards!

Assign the 3 public IP addresses from your ISP to your MT. From there, create srcnat rules and don't use action=masquerade. Use action=srcnat. Doing this will allow you to specify which public IP should be used for each subnet.

Eg:
/ip firewall nat
add action=src-nat chain=srcnat comment="Subnet 1" out-interface=WAN src-address=192.168.1.0/24 to-addresses=x.x.x.x
add action=src-nat chain=srcnat comment="Subnet 2" out-interface=WAN src-address=10.10.0.0/24 to-addresses=x.x.x.y
add action=src-nat chain=srcnat comment="Subnet 3" out-interface=WAN src-address=10.100.0.0/24 to-addresses=x.x.x.z

The x.x.x IPs are the IPs that would be provided by your ISP.

Assign the 3 public IP addresses from your ISP to your MT. From there, create srcnat rules and don't use action=masquerade. Use action=srcnat. Doing this will allow you to specify which public IP should be used for each subnet.

Eg:
/ip firewall nat
add action=src-nat chain=srcnat comment="Subnet 1" out-interface=WAN src-address=192.168.1.0/24 to-addresses=x.x.x.x
add action=src-nat chain=srcnat comment="Subnet 2" out-interface=WAN src-address=10.10.0.0/24 to-addresses=x.x.x.y
add action=src-nat chain=srcnat comment="Subnet 3" out-interface=WAN src-address=10.100.0.0/24 to-addresses=x.x.x.z

The x.x.x IPs are the IPs that would be provided by your ISP.

Thanks, friend! I'll try this.