dhcp-dns debugging help requested

["Jeff Vincent" <JVINCENT@novell.com>]

I had our dynamic dns working a few weeks ago, but I'm not sure when it
stopped and can't figure out what is failing.

I have a subnet X.Y.A.0/22 (X.Y.A.0/255.255.252.0) with static DNS
entries for each address I have available within MYDOMAIN.COM (about
1000 total).

I realized today that if I inadvertently set a dhcp cilent's host name
to a name that already exists as a static DNS entry
(hosta-1.MYDOMAIN.COM), the dynamic update will delete the entry when
the lease expires (duhrrr!).  So to get around the problem, I created a
new subzone called 'dhcp.MYDOMAIN.COM', and want to use that for all
hosts getting dynamic addresses.  However, nothing is getting updated in
my new subdomain.  It may have stopped working before I monkeyed with
it.  DHCP is working and handing out addresses, but the dynamic update
doesn't happen.

Can anyone offer any advice as to how to debug the problem?  I added
the '-d' option to the $NSUPDATE line inside /etc/dhcp-dns.conf.  No
errors are displayed when running ddns.cron.pl manually from the
command-line and there doesn't appear to be any relevant messages in
/var/log/syslog.  There are a number of lines generated in the file
/var/lib/dhcp-dns/nsupdate.data and it all appears to be good and
correct.

Here are my config files:

//**********Start: /etc/dhcp-dns.conf
# edit these for your own system

# this conf file is 'required()' into perl scripts so
# perl syntax applies.

$DDNSHOME="/var/lib/dhcp-dns";
$DHCPD="/var/dhcp/dhcpd.leases";
$DOMAIN="dhcp.MYDOMAIN.COM";
$NSUPDATE="/usr/sbin/nsupdate -d";
//***********End: /etc/dhcp-dns.conf


//**********Start: /etc/dhcpd.conf
option domain-name "dhcp.MYDOMAIN.COM";
option domain-name-servers service1.MYDOMAIN.COM,
service2.MYDOMAIN.COM;
option routers X.Y.D.254;
option ntp-servers X.Y.D.252 , X.Y.D.253;
option subnet-mask 255.255.252.0;

default-lease-time 600;
max-lease-time 7200;

subnet X.Y.A.0 netmask 255.255.252.0 {
        range X.Y.A.201 X.Y.A.254;
        range X.Y.B.201 X.Y.B.227;
        option broadcast-address X.Y.D.255;
        }
//**********End: /etc/dhcpd.conf


//**********Start: /etc/bind/named.conf
zone "MYDOMAIN.COM" {
        type master;
        file "/var/cache/bind/MYDOMAIN.COM.hosts";
        notify yes;
        allow-transfer {
                X.Y.D.253;
                };
        allow-update {
                X.Y.D.252;
                X.Y.D.253;
                127.0.0.1;
                };
        also-notify {
                X.Y.D.253;
                };
        };

zone "A.Y.X.in-addr.arpa" {
        type master;
        file "/var/cache/bind/X.Y.A.rev";
        allow-transfer {
                X.Y.D.253;
                };
        notify yes;
        also-notify {
                X.Y.D.253;
                };
        allow-update {
                X.Y.D.252;
                X.Y.D.253;
                127.0.0.1;
                };
        };

zone "B.Y.X.in-addr.arpa" {
        type master;
        file "/var/cache/bind/X.Y.B.rev";
        allow-transfer {
                X.Y.D.253;
                };
        notify yes;
        also-notify {
                X.Y.D.253;
                };
        allow-update {
                X.Y.D.252;
                X.Y.D.253;
                127.0.0.1;
                };
        };

zone "C.Y.X.in-addr.arpa" {
        type master;
        file "/var/cache/bind/X.Y.C.rev";
        allow-transfer {
                X.Y.D.253;
                };
        notify yes;
        also-notify {
                X.Y.D.253;
                };
        allow-update {
                X.Y.D.252;
                X.Y.D.253;
                127.0.0.1;
                };
        };

zone "D.Y.X.in-addr.arpa" {
        type master;
        file "/var/cache/bind/X.Y.D.rev";
        allow-transfer {
                X.Y.D.253;
                };
        notify yes;
        also-notify {
                X.Y.D.253;
                };
        allow-update {
                X.Y.D.252;
                X.Y.D.253;
                127.0.0.1;
                };
        };
zone "dhcp.MYDOMAIN.COM" {
        type master;
        file "/var/cache/bind/dhcp.MYDOMAIN.COM.hosts";
        allow-update {
                X.Y.D.252;
                X.Y.D.253;
                127.0.0.1;
                };
        also-notify {
                X.Y.D.253;
                };
        allow-transfer {
                X.Y.D.253;
                };
        notify yes;
        };
//**********End: /etc/bind/named.conf


The nsupdate.data file is now at 9k and growing.  I'm not sure if it
should shrink each time an update is successful or not.

Thanks in advance.

Jeff