Some patches

Martin Mares mj at
Mon Aug 25 11:49:21 CEST 2008


> If the broadcast address set using ifconfig is misconfigured,
> the canonical one (last address in the subnet) still works?

Yes, it should (see fib_add_ifaddr() in kernel ipv4/fib_frontend.c).

> BTW, what is the reason for this (from netlink.c:380):
>       if (i->ifa_prefixlen == BITS_PER_IP_ADDRESS - 2)                                                                                                                                  
>         ifa.opposite = ipa_opposite(ifa.ip);   
> ?
> AFAIK /30 mask does not need special handling.

The /30 networks can be considered point-to-point links in some cases,
so we maintain the address of the other end in the same way as we do
for unnumbered P-t-P networks.

I am not aware of any place in BIRD which relies on this (except maybe
the reference to `opposite' in proto/ospf/topology.c), but it definitely
should not do any harm.

				Have a nice fortnight
Martin `MJ' Mares                          <mj at>
Faculty of Math and Physics, Charles University, Prague, Czech Rep., Earth
A sine curve goes off to infinity or at least the end of the blackboard.

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