Monitoring IPv6-MAC mappings

[Simon Lockhart]

On Wed Apr 03, 2013 at 04:39:11PM +0100, Phil Mayers wrote:
> Maybe. We just do it over SNMP (or CLI scripting in some cases). The 
> code is pretty trivial.

+1

This is what I do - I'm is a slightly different environment, as I use DHCPv6
rather than SLAAC, but I do need to correlate the addresses back from DHCPv6
to MAC address. Originally I was extracting the MAC address from the ClientID,
but I found that many devices don't use the MAC address of the relevant
interface when constructing the ClientID (they seem to use the first MAC 
address on the device, irrespective of which interface they connect over), so
instead use SNMP to pull the MAC address from the IPv6 Neighbours table on
the router for the subnet. I then cache the (Subnet,ClientID) -> MAC mapping
to avoid hitting the routers with too much SNMP traffic.

Simon