config help - scaling problem

Marc Perea marccp at
Mon Mar 1 15:56:14 UTC 2010

Hello list,
I know there are quite a few helpful and ingenuitive folk who follow this list, and I'm hoping anyone can provide some insight on how I might better optimize my dhcpd.conf and/or system performance. My problem is that today it takes over a minute from when I type dhcpd until the daemon finishes loading into memory and is ready to service DHCP requests.
Additionally, when we perform periodic maintenance or upgrades, there are times when we require all clients to DHCP again, since our BRAS builds sessions and maintains state based on the DHCP process. Our Solaris Sun-fire V240 struggles to service anywhere from 1 to 5 DORA / second - with 10 thousand client requests to fulfill, you can see that it takes well over an hour before all clients get serviced.
Requirements: The business rules dictate that we provide a static IP to each client, and each client is identified by their unique, controlled and trusted agent.circuid-id inserted by company equipment. MAC is unusable for us due to spoofing concerns.
As such, I've so far built my dhcpd.conf like this: <snips>
class "" { match if (option agent.circuit-id = ""); }#Joe Smith 5551212
... #10 thousand more entries like this one ...

pool { authoritative; allow members of ""; range ww.xx.yy.zzz; }#Joe Smith 5551212
... #10 thousand more entries like this one ...
My first question - should I, and maybe could I, be using sub-classes instead of classes? Would that help me any?
Next, I modified syslog and added the hyphen so that (I hope) I am doing asynchronous logging to improve performance. Is there anything else I could do to enhance my server performance?
I also just implemented a ramdisk to store the dhcpd.conf and dhcpd.leases files, and invoking them with -cf and -lf hoping to improve performance as much as I can.
If anyone can see any changes or improvements I can make to better enhance my performance, it'd be greatly appreciated!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the dhcp-users mailing list