Automatic LAN Subnet Reassignment

[Paul D]

On 2022-02-21 22:38, Rich Brown wrote:
> There is a new RFC on the OpenWrt forum proposing "Automatic LAN Subnet Reassignment" https://forum.openwrt.org/t/rfc-automatic-lan-subnet-reassignment-upon-conflict-with-wan/120938 The RFC responds to the advice given at last week's OpenWrt-Adm meeting (https://etherpad.wikimedia.org/p/ZlZiTcud3wufcSX9-1jD)
> 
> The intent of the proposal is for the default configuration to assign a LAN subnet that avoids a conflict with the WAN subnet, and provide a mDNS name such at OpenWrt.lan for connections.
> 
> I have two requests:
> 
> 1) Please make comments on the technical merits of the proposal on the OpenWrt forum at the link above.
> 
> 2) If the proposal seems to make sense, please consider the process by which we would incorporate this into the main release (likely, not for 22.0x, but perhaps the next release?)
> 

I think this regards only IPv4. I propose that the RFC1918 nets on 
either side be in the same block, to avoid NAT, and try to retain 
routing: performance. A NAT choice might present security advantages, 
however.


Ideally one would consider configured (static) routes such that any 
chosen (sub)net does not collide with one further up/downstream.


No preference either way for .home.arpa. or .lan: both are sane, but one 
more to type than the other, although both available is good.

4.3 and 4.4 have importance, however:

https://www.rfc-editor.org/rfc/rfc8375#section-4