Re: Using x.x.x.0 and x.x.x.255 host addresses in supernets.

[Joe Provo <nanog-post () rsuc gweep net>]

On Tue, Jan 08, 2008 at 09:50:13AM -0500, Jon Lewis wrote:
> On Tue, 8 Jan 2008, Joe Provo wrote:
>
> > Yes.  Efficient address utilization is a Good Thing.
> >
> > > I realize that technically they are valid addresses, but does anyone
> > > assign a node or server which is a member of a /22 with a x.x.x.0
> > > and x.x.x.255?
> >
> > Great for router interfaces, loops, etc where you don't care that
> > broken or archaic systems cannot reach them, and where the humans
> > interacting with them should have no issues.
>
> Until you assign a .255/32 to a router loopback interface and then find 
> that you can't get to it because some silly router between you and it 
> thinks '.255? that's a broadcast address.'

See the qualifier "where you don't care that broken or archaic systems 
cannot reach them". If you have brokenness on your internal systems 
then yes, you'd be shooting yourself in the foot.


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