Netmask override: how to?

[pietwauters]

Hi,
I don't fully understand how Netmask override works.
I need the following configuration:
Addresses need to be like 172.20.x,y.
I have a bunch of IoT devices, all with a static (self assigned) IP address in the range: 172.20.xxx.1
All other devices need an address from the router such that

1. they have access to all IoT devices
2. they all have access to eachother
3. there are no IP address conflicts.

Is this possible and if so how should I modify the settings?

[dchristl]

Hello,

I'm not quite sure if I've understood everything. The network override determines which netmask and therefore which address range / number of IP addresses is used.
Your requirements are therefore not feasible. A connection between the IoT devices if they were all in the 172.16.x.x range. But then you would still have the problem with the IP address conflict. The router does not know which addresses are already assigned elsewhere.
But why don't you just try it out with one device?