I'm switching ISP for my home broadband and because of the switch I now have no broadband at home until my new ISP activates it.

"No worry" I thought, "My N900 and router will save the day". My router can accept a 3G usb adaptor for internet (it's a DIR 855) and my N900 can tether so the solution seemed simple, just connect my N900 to my router and all my computers will have internet. Except for some reason it doesn't seem to work. Has anybody else tried this or does anybody have some advice?

install DD-WRT on your router, set up a hotspot on the n900, make the router connect to your n900 via wlan
???
profit

Did you insert the right commands,username,password,host,etc..from your provider at the router?
can you see any logfiles at your router?

You can't install DD-WRT on the DIR-855 not the right chipset, trust me, if I could, I would, for the profit that is.

not sure, what commands should I enter? I'm on t-mobile uk. I just chose t-mobile from the drop down menu but I can enter

dial number
apn
username
password

manually to overide the default. What username and password should I enter?

aw damn, then my method goes down the drain
sorry, I saw "DIR" and instantly assumed it was the same as my router (DIR-600). my bad

How about installing Mobile Hotspot and using your N900 as the router?

Am I correct that your first attempt is to establish a wifi connection between N900 and router such that the other computers wire-connected to the router could access the internet through tethering? It should work unless your router does not route the traffic between the wlan and lan.

@retsaw
I can't set the DIR855 as a client bridge so my wired computers will have no way of connecting. The good thing about tethering to the N900 was that all my wired connections will instantly have a connection. As if nothing had changed on my network.

@9000
yep, you are correct. Though it's not really a wifi connection between the router and N900 but a USB one.
It just doesn't work though, I'm not entirely sure why. My WAN status shows as disconnected on the OLED display before I even try and connect through any LAN computers to the internet.

Anyway, my new ISP activated in the evening so at least I have broadband again, but it would be nice to get this working for future reference.

I've wondered this too, as I generally have problems if more than one computer connects to the n900 through MHS