[71969] in North American Network Operators' Group
Re: The use of .0/.255 addresses.
daemon@ATHENA.MIT.EDU (Stephen J. Wilcox)
Sun Jun 27 12:12:54 2004
Date: Sun, 27 Jun 2004 17:12:17 +0100 (BST)
From: "Stephen J. Wilcox" <steve@telecomplete.co.uk>
To: Peter Corlett <abuse@cabal.org.uk>
Cc: nanog@nanog.org
In-Reply-To: <cbmkjh$rpp$1@dopiaza.cabal.org.uk>
Errors-To: owner-nanog-outgoing@merit.edu
On Sun, 27 Jun 2004, Peter Corlett wrote:
>
> Stephen J. Wilcox <steve@telecomplete.co.uk> wrote:
> [...]
> > I currently have a few .255/32s with Cisco and Foundry products and
> > have various windows/linux/OSX machines that access them without
> > problems..
>
> Well, I'd expect Linux and OSX to do the right thing. It just seems to
> be Windows that makes a complete sow's ear of it.
>
> As to the IP addresses ending in 255 that are working from Windows
> boxes, would I be right in guessing that the first octet of the IP
> addresses in question is between 1 and 191?
Hi Peter,
actually no.. I just did a test right now, I'm at a friends and using an XP
machine connected via a cable modem.. my results arent entirely in agreement
with my initial post
I tested to both a "Class A" .255 we have and also to a "Class C" .255 we have
Class A: works on everything..trace, ping, ssh
Class C: spooky, traces up to the interface before the device. wont ping.
connections fail with Network error: Cannot assign requested address. But, this
same test works when tried from linux - possibly different behaviour between
icmp and udp on cisco??
From the hop-before-last (cisco 7206 12.2(14)S3) if i ping it seems to be
broadcasting out of the interface towards the .255 rather than unicasting, i
confirm this with a packet capture:
16:03:47.614187 Class-C.x.x.x > 255.255.255.255: icmp: echo request
the cisco reports correct routing of the Class-C /32
Steve
