Port forwarding 2nd dynamic IP (Hitron)

[Russ9]

Scenario: Hitron modem in bridged mode, shaw has unlocked the 2nd dynamic IP address. Two independant routers from the hitron modem, each with their own public shaw IP. External access to the public IP is as expected for the first (primary) IP, I can forward external ports, all good. The 2nd IP (which is also a public IP) gets no external traffic inbound. I tried opening ports on that specific router and nothing.... You can ICMP ping it externally, but inbound traffic originating from the outside world is blocked. Not a port forwarding issue, the same thing happens with an open machine on that port instead of a router, still nothing coming inbound. Any ideas? 

[mdk]

@Russ9 -- it is the Shaw cable-modem that is "enforcing" the limit of 2 public IP-addresses.  If you switch from your own router on the 2nd port to a computer on the same port, your computer will be asking for a THIRD public IP-address. So, after switching the hardware, disconnect the power-cord from the cable-modem, wait a few seconds, and reconnect the power-cord, and allow the cable-modem to restart. After the restart, the "counter" of public IP-addresses will be "zero", until your two devices (router on port 1, changed device on port 2) make requests to Shaw's DHCP-server for public IP-addresses.

Check the public IP-address on the WAN port on the router on the first port, and the public IP-address on the second port, to ensure that Shaw's DHCP-server has assigned a new lease, along with the TTL (Time To Live) value that is supplied with the IP-address.