Dhcpd response in peer

[Martin Hochreiter]

Hi!

We have a particular problem with dhcpd:

We are using a fail-over/load balancing configuration of the isc dhcpd.
Master machine is running on Suse linux enterprise (10.0, dhcpd 3.0.3)
with ldap support and is doing well.

The second machine is a Cent OS 5.2. Cent OS 5.2 packaged dhcpd has no
support for ldap, so i downloaded the original 3.0.5 dhcpd, patched it
with Brian Masney's ldap patch and Ari Edelkind's paranoia patch to get
ldap support and chroot support.

The dhcpd daemon runs stable with querying the ldap server in its cage but
it doesn't reply always to correctly to dhcp inquiries.

I check the response every 30 minutes with nagios's check_dhcp with an 
unicast
to the failover, but it does not respond everytime.

To check a possible failure of the check_dhcp script, i stopped the 
primary dhcpd
to see if the machines can get there adresses ... some do, some dont

Nagios and the non-working machines show DHCPDISCOVER and DHCPOFFER in
the logs of the failover peer but no DHCPACK's.

I really have no idea where I could start to troubleshot here -
can somebody give me a hint please?

- if somebody is asking why I use that "old" version of dhcpd: I didn't 
get a recent
  version of dhcdp compiled with Masney's ldap patch (that we really need!)

lg
Martin

---------------- primary dhcpd ------------------
ddns-update-style none;
ldap-server "homes";
ldap-port 389;
ldap-username "uid=Admin,ou=Users,dc=base,dc=ac.at";
ldap-password "XXXXXXX";
ldap-base-dn "ou=DHCP,dc=base,dc=ac.at";
ldap-method dynamic;
ldap-debug-file "/var/log/dhcp-ldap.log";

failover peer "dhcp-failover" {
  primary; # declare this to be the primary server
  address 10.0.0.1;
  port 647;
  peer address 10.0.0.2;
  peer port 647;
  max-response-delay 30;
 max-unacked-updates 10;
  load balance max seconds 3;
  mclt 1800;
  split 128;
}
-------------------------------------------------------------



---------------- secondary dhcpd --------------
ldap-server "xdaten";
ldap-dhcp-server-cn "xdaten";
ldap-port 389;
ldap-username "uid=Admin,ou=Users,dc=base=ac.at";
ldap-password "XXXXXX";
ldap-base-dn "ou=DHCP,dc=base=ac.at";
ldap-method dynamic;
ldap-debug-file "/var/log/dhcp-ldap.log";

failover peer "dhcp-failover" {
  secondary; # declare this to be the secondary server
  address 10.0.0.2;
  port 647;
  peer address 10.0.0.1;
  peer port 647;
  max-response-delay 30;
  max-unacked-updates 10;
  load balance max seconds 3;
  mclt 1800;
}
-------------------------------------------------------------