Re: Raspberry Pi as bridge

[Johnny Billquist <bqt%update.uu.se@localhost>]

On 2019-01-22 20:07, Jörn Clausen wrote:
> Hi!
>
> I am trying to use a Raspberry Pi running
>
> NetBSD armv7 8.99.30 NetBSD 8.99.30 (RPI2)
>
> as a bridge to extend my WiFi net to some devices. I have two NICs,
> usmsc0 (internal RJ45) and urtwn0 (WiFi USB). urtwn0 is up and running
> and works as desired. I have followed the bridge instructions in the
> NetBSD guides, i.e.
>
> $ cat /etc/ifconfig.bridge0
> create
> !brconfig $int add urtwn0 add usmsc0 up
>
> tcpdump on either interface shows that broadcast packages are passed
> between interfaces, but nothing else. A DHCP request coming in via
> usmsc0 from a device is visible on urtwn0 but is not passed on to my
> DHCP server.

I'm not sure you really have it working the way you think.

In my experience, WiFi works "funny". I've trying to do something 
related the last couple of days.

Broadcast packets are received fine by the wifi interface. However, 
sending packets out on a WiFi interface with a different source MAC 
address than the WiFi interface itself have seem to not go through.
So your observation about packets being received and forwarded on the 
box might not be enough evidence that it actually works all the way.

WiFi is not the same as ethernet, and in this particular instance it's 
painfully clear.

I'm no expert on WiFi, but if you can manage to get the WiFi interface 
into hostap mode, it should be possible to get it working, but how you 
actually achieve that (assuming your interface even can) is something I 
don't know...

> I have
>
> net.inet.ip.forwarding = 1

Not relevant as we are not talking about IP routing.

  Johnny

--
Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email: bqt%softjar.se@localhost             ||  Reading murder books
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