Impossible to setup port forwarding or NAT on Sky Business Hub BR440

[mightysven]

So I've been trying to set up NAT or DMZ to allow passthrough to some internet-facing services I run.

However, the Sky Business Hub (BR440) tells me whatever I enter is invalid.

The guide from Sky is no use either, as this simply outlines the process that I am following.

Starting with port forwarding, I'm opening a single TCP/UDP port.

Whenever I hit save, I always get the following message.

I then re-enter the values as the IP has been wiped out and receive the following message:

If I navigate to the port forwarding page none of the details that I save are present, however an entry with blank values has been created.

I have a Unifi network downstream, with the internet connection to the Sky Hub working, so I know there are no issues with the server IP I'm providing.

However, it doesn't appear to matter what I enter here, it simply won't let me set up port forwarding to an IPv4 host.

It's a similar story with DMZ. Regardless of the values I enter, I always get taken back to the same screen with no error message displayed after I hit save to setup the DMZ host.

I've tried all the usual suspects such as restarting/powering off the router to no avail. The same sequence of events happens every time I try.

I'd happily use a non-Sky router if it was supported, but I understand I won't get any help from Sky if there are issues with such a configuration.

The firmware version I'm running on the Business Hub is below: 

Software Version:1.2.46.R

Software Image Name:BR440-1.2.46.R

Has anyone had any joy with getting these common networking tasks working on the Business Hub? 

[jamesn123]

@mightysven 

Bit of an odd one. Dont think I've seen a post about port forwarding on the business hub yet.

Obvious one but have you tried a complete factory reset and trying again?

[mightysven]

I did a factory reset to start with a blank slate.

What I found was that you have to specify an IP address that is in the range of DHCP allocated addresses by the router for the DMZ or port forwarding to be configured.

If you try to add an IP address that isn't in this DHCP range you get strange errors like "invalid IP address", and nothing saves.

I had increased the start address for the DHCP range in order to have some devices with manually assigned static IPs on the network. This is why I hit this issue.

Instead of changing the start address for the DHCP range, you should reserve IP addresses for the devices you want to use a static IP for and leave the DHCP ranges unchanged.