[c-nsp] glbp migration to hsrp anycast

[Sascha Pollok]

Gents and Ladies,

[...]

>> Will all servers update their arp table, if the hsrp function propagates 
>> gratious arp.
>
> I've never seen this fail except on REALLY REALLY old things; Solaris 2.6 had 
> a problem, IIRC.

We saw firewalls of customers not accepting ARP-Replies when no ARP 
whohas was sent before. We debugged ARP and found out that it refreshes
its ARP-table every 30 minutes so we waited 2 seconds before end of the
30-minutes interval and made the switch so the new MAC was there once
the firewall expired its ARP cache.

Very annoying security feature ;-)

-Sascha