I’ve been discussing my issue with the technical team at Talk Talk who sadly are unable to assist me with what I feel should be a basic element of their router. They have made it clear they do not support the router or its firmware they upload to their devices and recommended I post the problem here.
I’m currently using the Sagemcom FAST 5364 under the latest version SG4K10001E00t and am trying to reserve internal IP addresses so that I may broadly catalogue similar devices together in their own range and ultimately control them independently. So in Advanced Settings à Talk Talk Wi-fi Hub à DHCP I have a button saying ‘Reserve IP Address’. When hitting this a red error message ‘invalid IP address’ appears 3 times on the page beneath my DHCP IP Address, Ipv4 Pool Start address, and IPv4 Pool End address. Equally, the same message appears if I were to try to change the DHCP IPv4 Pool Start and Pool End addresses.
Now I’m unsure whether this is a condition of the latest firmware but what I do know is that it previously worked a couple of months ago as I managed to reserve a particular IP address for a specific device using its MAC address. I know you are also able to reserve an IP address under each device connected to the router but this obviously only gives me the IP address that the device is currently using which may not always be satisfactory, plus if you revert to doing this and trying to alter the IP address later in the DHCP function explained above then the same error message similarly appears.
I’ve looked at a couple of suggestions here on the community, including one suggesting removing the whole IP address and not just editing the last couple of digits, but in my case this didn’t make any difference.
I'll be grateful for any other suggestions, or hopefully a fix for this issue.