dhcpd not updating Microsoft DNS servers

[Brazen]

I'm putting in an ISC DHCPD server to replace Microsoft DHCP server because it is a pain in the neck managing reserved hosts in Microsoft's DHCP.

Anyway, it won't add the clients that it assigns addresses for to the DNS servers. I've set the zones on the dns servers to accept secure and non-secure updates, and here is my dhcpd.conf:
--------------------
##### SERVER SETTINGS #####

ddns-update-style interim;
ignore client-updates;
update-static-leases on;

zone bucoks.com {
primary 192.168.100.2;
secondary 192.168.100.3;
}
zone 100.168.192.in-addr.arpa. {
primary 192.168.100.2;
secondary 192.168.100.3;
}

option domain-name "company.com";
option domain-name-servers 192.168.100.2, 192.168.100.3;

# 8-day leases
default-lease-time 69102;

# disable bootp
deny bootp;
#deny dynamic bootp clients;

##### SUBNET SETTINGS #####

subnet 192.168.100.0 netmask 255.255.254.0 {
option routers 192.168.100.1;
option subnet-mask 255.255.254.0;

range 192.168.100.0 192.168.101.254;

host server1 {
option host-name "server1.company.com";
hardware ethernet 00:XX:XX:XX:XX:XX;
fixed-address 192.168.100.4;
} # end of host

host server2 {
option host-name "server2.company.com";
hardware ethernet 00:XX:XX:XX:XX:XX;
fixed-address 192.168.100.5;
} # end of host

} # end of subnet
--------------------

I can't find anything about even attempting to update dns in the logs, just that the dhcp addresses were requested and acknowledged, and all static and dynamic clients are getting addresses just fine.

Any ideas? I'm not even sure if it's really not even trying to do the dns updates or if I just need to set something to get some better logging?

 

[Nothinman]

Have you tried doing a packet capture when a request comes in to see if there's any traffic going to the DNS server?

 

[Brazen]

no

 

[Nothinman]

Well that would probably be my first step. I've had dhcpd update BIND before but not MS DNS and I don't even have that config handy. There's also DNS specific event logs on the Windows side although I don't know if they'll be useful.

 

[her209]

I would check:

- to make sure its pointing to the Windows DNS server
- to make sure the client is set to update the pointer record in the DNS server

 

[Brazen]

Well that would probably be my first step. I've had dhcpd update BIND before but not MS DNS and I don't even have that config handy. There's also DNS specific event logs on the Windows side although I don't know if they'll be useful.

Using tcpdump on the dhcp server, it does not look like any traffic is being sent to either dns server. I tried with a static client and a dynamic client.

I would check:

- to make sure its pointing to the Windows DNS server

I did double check it is pointing to the correct addresses for the dns servers.

- to make sure the client is set to update the pointer record in the DNS server

I want the dhcp server to do the updating regardless of the client, so I don't see how that would be useful.

 

[Brazen]

Using tcpdump on the dhcp server, it does not look like any traffic is being sent to either dns server. I tried with a static client and a dynamic client.

scratch that. About 5 minutes after the dynamic client got it's address, this went through:

IP 192.168.100.2.netbios-dgm > 192.168.101.255.netbios-dgm: NBT UDP PACKET(138)

EDIT: Oh wait, that musts be a packet FROM the dns server sent out over the broadcast address.

 

[Nothinman]

That's just NetBIOS, probably looking for the master browser or something.

What version of Windows is the DNS server on and what is Dynamic updates for that zone set to allow?

Everything I can find is for doing ISC dhcpd->BIND and they all mention a key, so I'm wondering if dhcpd isn't trying to update the zone because it doesn't have a key defined.

 

[Brazen]

That's just NetBIOS, probably looking for the master browser or something.

What version of Windows is the DNS server on and what is Dynamic updates for that zone set to allow?

2008 R2. It's brand-spankin'-new.

Everything I can find is for doing ISC dhcpd->BIND and they all mention a key, so I'm wondering if dhcpd isn't trying to update the zone because it doesn't have a key defined.

I was wondering the same thing about the key. I think maybe next thing I'll try on Monday is set up a BIND dns server and try updating to it. I would prefer to stick with MS DNS, but maybe it's not going to be possible.

 

[scottws]

Maybe this will be helpful?

https://lists.isc.org/pipermail/dhcp-users/2008-November/007471.html