> On the other hand one could use intervals for key assignment.
> Every time a server runs out of keys it throws a warning at the admin
> and rejects further inserts until it gets a new key interval.
> It's a way to go at least with a low number of servers.
Maybe even give a warning some time _before_ you run out of keys...? ;)
You should never run out of keys. Every time you sync, you also check if
there are many keys left to use... if you sync once a day, as soon as you
have less than 10 times the expected daily usage of keys left to use, you
request a new set of keys.
You still would have to handle duplicates.