Michael Rack wrote:
You have to setup a bridge on your linux-router and assign every dynamic created ppp-interface to that.

        brctl addif br0 pppx

Configure DNSMASQ to listen on the bridges interface.

        interface=br0
        bind-interfaces

And well, you're done.

Cheers,
Michael.

Thanks for the suggestion, Michael.

I have tried it, but unfortunately it doesn't work :(.
The command "brctl addif br0 ppp0" fails with "can't add ppp0 to bridge br0: Invalid 
argument". It looks like point-to-point interfaces can not be added to a bridge (I tried also 
with a TUN device, just to see if it could be added, and got the same error message).
--
Kind regards,
Sergei.


Am 17.10.2009 14:04, schrieb Sergei Zhirikov:
Hi,

I'm using dnsmasq as a DHCP and DNS server on my Linux home gateway, which is 
also a IPSec/L2TP VPN server. For IP address allocation for the VPN PPP tunnels 
I use ppp-dhcpc plugin, which pretends to be a DHCP relay and requests IP 
addresses from dnsmasq. That part works fine.

However, when the PPP link has been established the VPN client (a Windows PC in 
my case, but I don't think it's relevant) send DHCPINFORM request to the 
broadcast address 255.255.255.255. That request reaches the Linux gateway via 
the PPP link, but dnsmasq does not reply, because it can see that the request 
is coming from an interface it is not configured to serve.

I would really like dnsmasq to reply to those DHCPINFORM requests coming in 
through the PPP links, but I haven't been able to configure dnsmasq for that. I 
can't tell it to serve the PPP interface, because the interface name is 
assigned dynamically (thus not known in advance). I can not tell dnsmasq to 
serve all interfaces with some exceptions either, because then the list of the 
exceptions would have to contain dynamically assigned names.

I have tried some tricks with iptables. Tried to use "-j ROUTE --iif ifname" to 
make the packets appear coming form another interface with a fixed name that dnsmasq is 
configured to serve, but dnsmasq still does not reply as if it somehow can see the 
original interface name.

I have tried to use a pair of VETH interfaces to route the incoming packets to 
one end of the virtual tunnel so that they would appear to dnsmasq coming out 
of the other end, but that didn't work, because I didn't manage to get the 
routing work the way I wanted (perhaps, because I lack necessary knowledge 
about advanced routing).

I would appreciate any kind of help with this problem.

Thank you,
Kind regards,

Sergei.


_______________________________________________
Dnsmasq-discuss mailing list
[email protected]
http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss


Reply via email to