Hi there

I am trying, for aeons (at least 3 years on and off), to use a laptop under linux as a Access point. I have tried this in all flavours and so far failed.

The two systems are both in ad-hoc mode, can connect to eachother.
If I assign them IP addresses, they can ping eachother, although sometimes, for no reason at all, all packets just get lost for like 3 seconds.

Now I try to build a bridge on the sytem that is also connected to a wired network, in order to let the other wireless system route over it.

(this is all happening on System A)
I create the bridge:

brctl addbr br0


ifconfig eth0 0.0.0.0 up
ifconfig wlan0 0.0.0.0 up
I also switch on promisc on both, because I heard that that is necessary.

I then add the interfaces to the bridge:

brctl addif br0 eth0
brctl addif br0 wlan0

I change the mac address on the bridge, because it is the same as eth0, which cannot work.

I properly get a new IP address from my DHCP server when doing
dhclient br0

let's say I get 10.10.20.45/24 on br0

the external system B from which I try to connect to the Bridge on sytem A, which I give the IP 10.10.20.19/24 now reports Destination Host unreachable.

When checking with wireshark on br0 on System A, I get the following conversation:

ARP: from 10.10.20.19: tell me how I can reach 10.10.10.45, please tell 10.10.20.19.

APR: from 10.10.20.45: 10.10.10.45 is on xx:xx:xx:xx:xx

so my system is getting the answer necessary, but for some reason, cannot get through to it. the bridge is not bridging at all.
I switched on STP and off, seems to make no difference at all. No firewall is active.

Is there a way to troubleshoot the bridge? Why is it not letting anything get through?

*bump*

Markus

I have had a success now, a broadcast for a IP number gets through to the DHCP server over system A, the client gets the IP number over the bridge, but after that, same problem.

It seems to me, that Ethernet stuff works, broadcasts, APR requests etc.. but anything IP does not and does not get forwarded over the bridge.

strange...

I don't get it. Seems to be impossible to solve this.

Is there ANY card that you can use as a AP? Or do I have to recommend to anybody to just give up? No Linux system can be converted into an Access point?
The forums are full of the error destination host unreachable. Anybody care to explain exactly what that means?

Markus

I'm actually working on the same thing. I have a rt61pci card.

00:09.0 Network controller: RaLink RT2561/RT61 802.11g PCI
Subsystem: RaLink EW-7108PCg
Flags: bus master, slow devsel, latency 32, IRQ 18
Memory at dc040000 (32-bit, non-prefetchable) [size=32K]
Capabilities: [40] Power Management version 2
Kernel driver in use: rt61pci
Kernel modules: rt61pci

That is the lspci -v info. This is setup as a ap with wpa2.
The next thing I'm going to work on is setting it up as a bridge. I'm gonna bridge eth1 and wlan0, so that my lan is one network, not one for wifi and one for cable. Eth0 will be the iface to inett.