[177118] in North American Network Operators' Group
Re: Charter ARP Leak
daemon@ATHENA.MIT.EDU (Larry Sheldon)
Mon Dec 29 20:21:42 2014
X-Original-To: nanog@nanog.org
Date: Mon, 29 Dec 2014 19:21:28 -0600
From: Larry Sheldon <larrysheldon@cox.net>
To: nanog@nanog.org
In-Reply-To: <ZVcQ1p00K1cZc5601VcSbj>
Errors-To: nanog-bounces@nanog.org
On 12/29/2014 11:35, Brett Frankenberger wrote:
> On Mon, Dec 29, 2014 at 12:27:04PM -0500, Jay Ashworth wrote:
>>>
>>> Valdis, you are correct. What your seeing is caused by multiple IP
>>> blocks being assigned to the same CMTS interface.
>>
>> Am I incorrect, though, in believing that ARP packets should only be visible
>> within a broadcast domain,
>
> broadcast domain != subnet
It surprises me that in this day and age, in a forum like this that has
an active thread about kids being taught archaic concepts, we see
language like "broadcast domain != subnet" and a perceived need to
explain it.
[no longer germane material deleted to reduce excess baggage charges]
> int ethernet 0/0
> ip address 10.0.0.1 255.255.0.0
> ip address 11.0.0.1 255.255.0.0 secondary
> ip address 12.0.0.1 255.255.0.0 secondary
>
> The broadcast domain will have ARP broadcasts for all three subnets.
This are not "subnets"! They are IP addresses in three different IP
networks.
> Doing it over a CMTS doesn't change that.
Communication here perceived as hostile is apologized-for.
--
The unique Characteristics of System Administrators:
The fact that they are infallible; and,
The fact that they learn from their mistakes.
Quis custodiet ipsos custodes
