DHCP problem in a complex scenario with lease events

Marc Perea marccp at srttel.com
Tue Oct 20 15:35:30 UTC 2009

Hi Christian,
I understand your dilemma and I don't know if there is an answer for #1

For #2 though, I'm sure you could make a class that matches the hardware address and then assign a pool (of as small as a single IP) to that class. I think you could also add several hardware address matches (using OR logic) and tie those to a single pool, if I'm not mistaken. This is exactly what we're doing at my shop, although we're matching on option 82 information since a MAC can be spoofed, but nonetheless, it does work and trigger the events you would like to execute on.

Unfortunately, and this may or may not be a problem for you, we've found that this solution tends to scale very poorly, since we are building 1 class for every client. Since there is no SIGHUP type of signaling to dhcpd to make it aware of config changes as we add new clients to reload the config on the fly, the daemon must be restarted often, and as we near 10,000 classes it is taking >10 seconds per daemon restart for the server to come back up. For us, that's becoming a problem - for you it may not be.

Good luck!


More information about the dhcp-users mailing list