On Wed 31 Mar 2021 at 10:45:59 (-0400), Marc Auslander wrote: > Anssi Saari <a...@sci.fi> writes: > >Brian <a...@cityscape.co.uk> writes: > > > >> Now - could I use this non-internet-capable router as a switch? ↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑ > > > >Probably. Usually LAN ports on a router are setup as a switch. The > >router may have a DHCP server running though which you may want to > >disable.
That's precisely the scenario I have here, posted in https://lists.debian.org/debian-user/2021/02/msg00603.html where it's the second diagram. Reason, the same or similar: a failed WAN port. But it's ideal for radiating to the living half of the house, and all its ports are active as well. > In my experiance, you should put the router into access point mode, > connect your lan to the wan port, and then use the lan ports as > additional ports. Some routers get confused when they think they are > routing even though they can't reach the wan. And remember to turn off > WiFi unless it is far from your primary router and you want to extend > your WiFi network. Yes, you only *have to* switch to AP if you have a working WAN port, which you're connecting to the primary router. It does no harm either way in Brian's case (or mine), with no functional WAN port. I don't know that the secondary router gets "confused" if you leave it in non-AP mode (when you are using the WAN port), but I assume that a host on the primary router should be seen as an outsider if it tries to connect to one on the secondary router, which would be a problem. > Also, make sure you set the IP address of the router to one on your lan > that's not in use and not in the DHCP range of your primary router. I > normally use .2 for this purpose. The primary router has the secondary one at a reserved address— actually that's the case for all the hosts in the house. (Neither router is capable of acting as a DNS server.) The wifi settings are identical for both, and hosts just connect to whichever gives the stronger signal. But going back to the OP's original scenario, a broken¹ router would be an ideal solution for linking two wifi laptops, with no possibility of accidentally joining the Internet (horrors!). ¹ Is this a common mode of failure? My guess would be that, plus the radio part. (Note: nowhere am I talking about modems.) Cheers, David.