<div dir="ltr">are you using non-authoritative ? I'm not sure exact way to implement it in your environment, but it might work. -greg <div><div class="gmail_extra"> <div class="gmail_quote">On Thu, Jan 3, 2013 at 8:20 PM, solarflow99 <<a href="mailto:solarflow99@gmail.com" target="_blank">solarflow99@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Thanks for the tip, I got it working, but still couldn't stop the dhcp servers from interfering with each other. I see a lot of messages like this in syslog: DHCPDISCOVER from 1c:b0:94:31:20:98 via eth0: network <a href="http://192.168.2.0/24" target="_blank">192.168.2.0/24</a>: no free leases It might be a client side problem for not ignoring the NAK offer and picking up the right one from the other dhcp server, since some clients do work. <div class="HOEnZb"><div class="h5"> On Fri, Dec 28, 2012 at 9:21 AM, Greg Swift <<a href="mailto:greg@nytefyre.net">greg@nytefyre.net</a>> wrote: > > > > On Thu, Dec 27, 2012 at 7:41 PM, solarflow99 <<a href="mailto:solarflow99@gmail.com">solarflow99@gmail.com</a>> wrote: >> >> I have been testing with a second dhcp server on the same vlan, and >> wanted to limit the scope to only serve out to clients that have mac >> addresses that start with the same 3 octets, something like this >> maybe? >> >> >> class "custom-clients" { >> match if substring (option dhcp-client-identifier, 00:50:56); >> } >> >> deny unknown-clients; >> > > you are very close. if you search for 'isc dhcp match vendor' you should > get a lot of helpful information. You can simply use the hardware address > rather than an option. Plus unknown-clients refers to systems that do not > have a host entry in your file. In this case none do, so all clients would > be denied. You can either do an allow block: > > or > > class "good" { > match if substring(hardware,1,3) = AA:BB:CC; > } > > allow members of "good"; > > > > > or a deny block > > > class "bad" { > match if not substring(hardware,1,3) = AA:BB:CC; > } > > deny members of "bad"; > > > In an ideal world they work the same, but test it out and see how they do > for your use case. > > -greg > > </div></div><div class="HOEnZb"><div class="h5">> _______________________________________________ > rhelv6-list mailing list > <a href="mailto:rhelv6-list@redhat.com">rhelv6-list@redhat.com</a> > <a href="https://www.redhat.com/mailman/listinfo/rhelv6-list" target="_blank">https://www.redhat.com/mailman/listinfo/rhelv6-list</a> _______________________________________________ rhelv6-list mailing list <a href="mailto:rhelv6-list@redhat.com">rhelv6-list@redhat.com</a> <a href="https://www.redhat.com/mailman/listinfo/rhelv6-list" target="_blank">https://www.redhat.com/mailman/listinfo/rhelv6-list</a> </div></div></blockquote></div> </div></div></div>