Re: Routing Problem - Need Help

[Claudio Jeker <cjeker_(_at_)_diehard_(_dot_)_n-r-g_(_dot_)_com>]

On Wed, Feb 23, 2005 at 04:38:58PM -0800, Karsten McMinn wrote:
> On Wed, 23 Feb 2005 22:33:14 +0100, Claudio Jeker
> <cjeker_(_at_)_diehard_(_dot_)_n-r-g_(_dot_)_com> wrote:
> > While your example needs to fail I don't see a reason why
> >   xl0:                10.0.0.254/24
> >   xl1:                10.0.50.99/16
> > needs to fail.
> 
> because this isn't exactly a cisco gsr here. the more specific doesn't
> get loaded by default, although logic says it should, the larger is
> king in the openbsd routing table. also fyi, Cisco doesn't let you
> overlap on interfaces either. I don't want to get into ipv4 design
> limitations, suffice it to say that it could work if one wanted to
> tweak source.
> 

This is not fully true. In this example only 10.0.0/24 is loaded as xl0 is
added first. Currently the first wins and this is bad.
Sure running a system with overlapping interfaces is not fine art. All
hosts on the larger net need to have a static route for the more specific
net.

Side note: using 10.0.1.254/24 for xl0 will not show this behaviour. In
this case both routes will be added.
-- 
:wq Claudio