dhcp migration issues

[Terry L. Inzauro]

List,

I've recently migrated off a DHCP appliance to ISC DHCPD and for the most part, there were no issues.  It has been a week
since the migration and now I'm seeing some messages like this.



2009-09-03T08:22:00-05:00 <local7.err> dhcpd.server.local dhcpd: Reclaiming abandoned lease 60.164.174.176.

2009-09-03T08:22:00-05:00 <local7.info> dhcpd.server.local dhcpd: DHCPDISCOVER from 00:04:5a:6e:02:86 via 60.164.174.163

2009-09-03T08:22:00-05:00 <local7.info> dhcpd.server.local dhcpd: DHCPOFFER on 60.164.174.176 to 00:04:5a:6e:02:86 via
60.164.174.163

2009-09-03T08:22:00-05:00 <local7.info> dhcpd.server.local dhcpd: DHCPREQUEST for 60.164.174.176 (172.16.1.2)from
00:04:5a:6e:02:86 via 60.164.174.163

2009-09-03T08:22:00-05:00 <local7.info> dhcpd.server.local dhcpd: DHCPACK on 60.164.174.176 to 00:04:5a:6e:02:86 via
60.164.174.163

2009-09-03T08:22:02-05:00 <local7.err> dhcpd.server.local dhcpd: Abandoning IP address 60.164.174.176: declined.

2009-09-03T08:22:02-05:00 <local7.info> dhcpd.server.local dhcpd: DHCPDECLINE of 60.160.174.176 from 00:04:5a:6e:02:86 via
60.160.174.163: not found


furthermore, my leases files is riddled with this garbage:
grep 60.164.174.173 /var/lib/dhcp3/dhcpd.leases | wc -l


lease 60.164.174.176 {
  starts 4 2009/09/03 12:52:03;
  ends 6 2009/10/03 22:52:03;
  cltt 4 2009/09/03 12:52:03;
  binding state active;
  next binding state free;
  hardware ethernet 00:04:5a:6e:02:86;
  uid "\001\000\004Zn\002\206";
}
lease 60.164.174.176 {
  starts 4 2009/09/03 12:52:03;
  ends 4 2009/09/03 12:52:05;
  tstp 4 2009/09/03 12:52:05;
  cltt 4 2009/09/03 12:52:03;
  binding state abandoned;
  next binding state free;
}


Now, if I were a gambling man, I'd say there are clients that still have leases from the previous dhcp server, but the new
DHCP server doesn't know anything about them and tries to assign an address thats currently in use.  I've tried pinging the
addresses to no avail(clients may be firewalled) and the router that connects them can't send an arping.

Where/How do I begin resolving this issue?


best regards,

_Terry