Cisco FPR1010 with multiple WAN address

[Jh96]

Hi there!

Our company use MikroTik RouterBoard since 5-6 years ago.. we got 3 different public IP address from ISP. 

Example: 

111.222.333.444 - this is our first IP address, LAN clients communicate with this address, and our VPN clients connect this IP.

222.333.444.555 - this is our secondary IP, it is only and exclusively used by our Exchange server for outgoing and incoming mail and for the webmail service.

222.333.444.556 - our third public IP address, it is only used by our IP PBX 

In the MikroTik can we configure multiple WAN IP address to 1 interface (MikroTik got the 1st IP address from ISP with DHCP, and the 2nd and the 3rd IP address can we configure by static), but we can't configure same in the FPR (FDM). If we add the PPPoE interface username and pwd, the FPR got the 1st IP - 111.222.333.444, but how to configure the 2nd, and the 3rd IP? If we add subinterface, static IP, and the mask is 255.255.255.255 or 255.255.255.254, i got an error message on the deployment ("BAD MASK")... but 255.255.255.0 is not solution, because we add one subinterface, 222.333.444.555 and mask 255.255.255.0, no problem, after we try add the second subinterface, 222.333.444.556 and 255.255.255.0 mask, got an error, that the mask is incorrect...

Whats next?

[Flavio Miranda]

Hi

Subinterface could be an alternative but you need to not use overlaping network.

Example

If you have the network 192.68.1.0/30  you can use only the ip address 192.168.1.1 and 192.168.1.2 with the mask 255.255.255.252

Then, the next subinterface must be the next network 192.168.1.4 with the IP address 192.168.1.5 and 192.168.1.6 with mask 255.255.255.252

So on and so forth.

It seems to me you are trying to use overlap networks and the firewall not allow it.

[Jh96]

Yes, because our second and third public IP address is x.x.x.195 and x.x.x.196...

[Flavio Miranda]

But will depend on the mask, which mask is it?

I mean, different ISP was providing you the same IP address? only change the last octet?

[MHM Cisco World]

Friend config BD'

Fpr public IP will be assign to bvi interface

And other two two public IP you can assign to any device connect to fpr.

[Jh96]

We get 3 different public ip from 1 isp. I made a lame drawing to see if it's more understandable what I want to solve.

[MHM Cisco World]

I get it, you hide the public IP so I am not sure are three public IP in same subnet ??

[Jh96]

Yes, same subnet, the "x.x.x" part is the same for both

[MHM Cisco World]

friend then ONLY one interface need public IP, and two other Public IP you can use in NATing, not need to assign to to interface nor subinterface.
what is important that 
FPR have subnet include three public IP 
FPR have ONE interface in that Subnet 
the ISP official assign these IP to you. 

Go ahead config only one interface and use other two public IP in your NAT 

[Jh96]

thx, i try it