Re: [B.A.T.M.A.N.] single IP for multiple interfaces

Marek Lindner
2007-11-20T12:24:34Z

Hi,

> Works perfect, we use for instance the WRAP-boards in our network with
> two WIFI- and one LAN-Interface, all three having the same IP.
> The related patch is at
> http://titan.www.opennet-initiative.de/olsrd_patches/mipip.patch, but
> its since a while part of olsrd.

I read the patch and without knowing the olsrd code I would say that you
operate on interface names instead of IPs. But I see some problems here:
- How does this work in a mixed environment ?
- More important: The routing table operates on IP addresses and not on
interface names. Even if olsrd can distinguish your interfaces by name the
kernel can't.

Imagine: You have a node A with 2 Interfaces and node B can hear both
interfaces but one better than the other. The routing table entry would look
like that "<destination> via IP_of_node_A" whereas the kernel can't send the
packet to a distinct interface of A. Whatever interface of A responds first
to your ARP query will get all data packets and thus you may end up with
using lossy links.

I don't see anything to solve that in this patch.

Regards,
Marek