So the setup looks like this:
There is a main WLAN-router/modem which is connected to the internet and serves the lower floor with WLAN. Now upstairs I have a second WLAN-router/modem (I will call it router two from now on). A normal ethernet cable is plugged in in router two in one of the four ethernet ports and also in one of the four ethernet ports in router one. Since I don't want router two to act as a router but rather as an WLAN access point I set the routing mode to bridge in the admin interface. I did also disable it's dhcp server.
Now when I connect to router two via WLAN I get a correct IP (in the range of router one's dhcp configuration) and I can also ping router one for about 5 seconds. But then the connection seems to be lost. The strange thing however is that I can ping from a computer connected to router one onto the computer at router two but not in the other direction.
Edit: Next step
I had another WLAN router laying around and tried the exact same thing and it worked. It is a different model so I think it has something to do with how the router routes I guess. Now the problem is that this router which is working is pretty old and therefore has some undesirable effects like low range. So now that I know that its a problem of the router and not of the general setup do you have any ideas what could be the problem with the other router? I can still ping from router one all devices which are connected to router two but can not ping from the devices connected to router two ... not even onto the first router. Also ping to the Google DNS won't work so it's not a DNS problem. Any ideas?
Systems:
- Non-working router: Zyxel P-660HN-F3Z with ZyNOS Firmware Version: 3.70(BJQ.1) | 04/22/2010 DSL Firmware Version: Amazon_se_ADSL 3.1.1.1.0.2 21/9 8:54
- Working router: LinkSys WAG54GS 1.1