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	Wed, 16 Apr 1997 18:47:45 +0800 (WST)
Date: Wed, 16 Apr 1997 18:47:45 +0800 (WST)
From: Adrian Chadd <adrian@obiwan.psinet.net.au>
To: Alec Kloss <alec@d2si.com>
cc: Guy Helmer <ghelmer@cs.iastate.edu>, freebsd-questions@FreeBSD.ORG
Subject: Re: Subnets of all 0's/all 1's
In-Reply-To: <199704151739.MAA25341@d2si.com>
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> each.  Now, I realize that my servers (had I more than one) are eating
> up a bunch of bandwith talking with each other, so I want to isolate
> them on their own network.  Say I take all the hosts in the range
> xxx.xxx.xxx.64 to xxx.xxx.xxx.95 and set their netmasks to be
> 255.255.255.240, 16 networks of 16 hosts each.  With proper
> configuration, I expect this would work with existing software.  
>
I've already done this :)
Well..
At work I have three subnets on the same C-class for three physical
networks, all coming together at one point (Fbsd machine w/ 3 ether
cards). 

The ips are 203.62.152.0-31, 203.62.152.32-63 and 203.62.152.64-95.
Then I have 203.62.152.96->127 "blank" (its allocated for someone upstairs
next month), then I have 128-> 191 for something, and 192->256 subnetted
into 8 and 16-IP subnets (for modems). All in all, a very chopped up
C-class :) (not that I needed to conserve space, but..)

And from the router, its announced to the freebsd gateway box
as a single route, ie 203.62.152.0/24 (==netmask 255.255.255.0).

> Well, I already use hosts on the "reserved" subnet in the range
1-31 > without any problems.  Anyone out there have a definitive answer?
> 
> 

Also (please don't quote me on this :) isn't the RFCs you quoted from the
classful-routing days?

Remember now we have classless routing, no more fixed subnet masks.
After I tell my cisco's this, they quite happily do what I tell them.

Hope this helps, if not tell me and I'll try to explain a tad more (if I'm
not grossly mistaken myself..)

Adrian