Re: Labels people, and read them!
And you never had the situation where a client changes it's IP every minute because it constantly jumped between the two DHCP servers which were active at the same time but serving different parts of the same scope
They won't unless something is seriously wrong. A standards compliant DHCP client will NOT switch servers (and hence IP pool) unless it's "home" server is offline. As the lease runs down, the client will unicast a renewal request to the server from which it got it's lease - the other server will not get a look in as it won't even see the packet. If your lease times are reasonably long (IIRC, Windows defaults to something like 8 days) then most clients will simply renew their lease at boot-up in the morning and then do nothing during the rest of the day. Some "not very sticky" clients may switch pool at this point - by simply broadcasting for any lease, rather than requesting their previous lease.
Windows clients go further, and are very very sticky about their leases - which is itself a PITA at times.
Biting the hand that feeds IT
