Gah... that's what I get for not going to sleep until 7AM. ;)
Yes, those are both the scenarios I had thought of, but my brain must
have been dozing when I replied earlier.
I think beating the IFMAP server up is probably the wrong solution...
What I am going to do (and what I had considered last night) is freeze/
thawing a data structure that is a key/value pair of IP/MAC and having
my script load that and save it every time a change is made.
The thing that makes that ugly is that I'll need to use file locking
to prevent race conditions. It's probably not a bad thing. Since any
request coming in from the DHCP server is forked this should actually