Subject: Re: MAC Address Tracking via DHCP6

From: "Rajiv Asati (rajiva)" <[email-masked]>
Date: Thu, 31 Jan 2013 17:26:42 +0000

There is a better way out to track the IPv6 addresses used by the hosts
(via SLAAC or static) -

http://tools.ietf.org/html/draft-asati-dhc-ipv6-autoconfig-address-tracking

Cheers,
Rajiv

-----Original Message-----
From: Philipp Kern <[email-masked]>
Organization: The Debian Project (http://www.debian.org)
Date: Wednesday, December 12, 2012 10:37 AM
To: Brian Hamacher <[email-masked]>
Cc: "[email-masked]" <[email-masked]>
Subject: Re: MAC Address Tracking

>On Tue, Dec 11, 2012 at 04:04:14PM -0600, Brian Hamacher wrote:
>> I am looking for a good way to track my users MAC Addresses.  I have a
>> test DHCPv6 server up and running ISC 4.1.1-P1.  When I look through my
>> DHCP logs as well as my leases file I do not see the client MAC Address
>> anywhere.  Do I need to enable an option to allow this to be logged?  I
>> am looking to figure out how I can track what user had what IP Address
>> at any given time.  The MAC Address is traditionally how I have done
>> this.
>
>One way would be to poll your routers' ND tables (like fetching ARP tables
>in IPv4). As soon as you use relaying you most certainly won't get a
>useable MAC address from your client, even though it might be possible in
>the same network segment. (The MAC address is not copied from the wire
>into the new relayed packet sent by the router to your server.)
>
>DHCPv6 uses the so-called client identifier extensively and not the MAC
>address anymore. So you cannot do any static assignment based on MAC
>addresses.
>
>Kind regards
>Philipp Kern