[tlug] Problems with au ADSL/network setup

["Stefan A." <stefan.a@example.com>]

Hi all,

A friend of mine is having problems with his home internet connection
and asked me for help, but I can't for the life of me figure out what
is wrong and so I was hoping someone on here may be able to give advice.

The problem: My friend uses some older type of au ADSL with a modem
which he rented from his provider. The modem only has one Ethernet LAN
port and no wifi (au charges extra for wifi), so he connected an IOData
WN-G54/R4 router to the modem a few years ago to share his connection
between several local systems (by cable) and his smartphone/tablet
(wifi). This worked well until a few months ago, when he couldn't reach
his router's admin interface anymore. Suspecting that the router was at
fault, which was by now pretty old and didn't support WPA2 anyway, I
gave him a spare Buffalo WHR-G301N router. But after hooking it up to
his modem, I was baffled to find that the same thing happened. The
modem seems to overwrite the IP addresses allocated by the router(s)
shortly after connecting them, making it impossible to reach the
router's admin interface. Wifi is still working, but my friend reports
that it breaks down occasionally, making a reboot of the (Buffalo)
router necessary.

Although I played around with the modem and the routers for some time,
I was unable to determine what was going on. Frankly, I am at a loss at
how such a weird combination of problems can even occur, although
hardware issues (or gremlins) may play a role here. I was about to
recommend throwing out all that old garbage, upgrading to Hikari (since
his connection is quite slow) and getting a new router from au,
although that means they would charge him extra for wifi, which I find
petty. What are your thoughts/recommendations?

Stefan
-- 
Stefan A. <stefan.a@example.com>