DNS progagation 1

[kHz]

I am not a DNS expert and need someone to explain to me this problem.

Our sister company on the east coast has a primary DNS server. If there are any additions/deletions/changes, they make them and the changes are supposed to propagate
to our local DNS server. But the problem is this: a new server pluto was added and the DNS entry was made back east. Now if I am on a server locally I can ping pluto and telnet, etc., without any problem. But the DNS entry for pluto does not appear in the local zone file.

If I do an nslookup and pluto it returns:
Server: mars.galaxy.org
Address: 192.168.1.10

Name: pluto-mgt.galaxy.org
Address: 192.168.1.222
Aliases: pluto.galaxy.org

And this is my local /etc/resolv.conf :
domain galaxy.org
nameserver 192.168.1.10
nameserver 192.168.2.20 # this server no longer exists, but cannot get anyone to let me remove it!
search galaxy.org

Doing an nslookup is going to the server, mars , the local DNS server, but as I mentioned the entry for pluto doesn’t exist locally in the mars zone file. My assumption is that since pluto cannot be found locally it is searching the entire galaxy.org domain for the entry, which it finds on the DNS server on the east coast. Is my assumption correct?

My other question is, if they make a change to their DNS server out east and it is supposed to propagate to our server, why is the entry for pluto not in the local zone file?

Thanks!

 

[ChrisAC]

When you say that a server pluto has been added, what domain is it in? Is it not pluto.galaxy.org?

"But the DNS entry for pluto does not appear in the local zone file."

Which zone file are you looking in?

"the entry for pluto doesn’t exist locally in the mars zone file"

"mars" would not be a zone. Is it mars.org, mars.galaxy.org?

Basically, what zone file was "pluto" added to on the primary DNS server or was a new zone created (pluto.org??)

Chris.

**********************
Chris A.C, CCNA, CCSA
**********************

 

[kHz]

When you say that a server pluto has been added, what domain is it in? Is it not pluto.galaxy.org?

It is pluto.galaxy.org as shown in the nslookup.

Which zone file are you looking in?

galaxy.zone which is the one referenced in /etc/named.conf on server "mars".

zone "galaxy.org" in {
type master;
file "galaxy.zone";
};

"mars" would not be a zone. Is it mars.org, mars.galaxy.org?

No it isn't a zone. mars is the local DNS server in galaxy.org

Basically, what zone file was "pluto" added to on the primary DNS server or was a new zone created (pluto.org??)

pluto would have been added to the galaxy zone on the primary DNS server.

 

[ChrisAC]

So the host pluto was added to the master galaxy.org zone file on the primary DNS server, yes? And your local DNS server is mars.galaxy.org, yes?

So you have asked your local DNS server mars.glaxy.org the IP address for pluto.galaxy.org. It appears to have given you an answer:

Server: mars.galaxy.org
Address: 192.168.1.10

Name: pluto-mgt.galaxy.org
Address: 192.168.1.222
Aliases: pluto.galaxy.org

However, if it did get that from the primary DNS server then the question is, why hasn't the slave transferred the new zone. The answer looks to be with the configuration of your slave server, mars;

zone "galaxy.org" in {
type master;
file "galaxy.zone";
};


You first said;

"Our sister company on the east coast has a primary DNS server. If there are any additions/deletions/changes, they make them and the changes are supposed to propagate"

But your local DNS server thinks that it is the master for this zone, therefore it won't attempt a zone transfer. If your server is slaving for the zone galaxy.org, you should have "type slave", and not "type master".

Chris.

**********************
Chris A.C, CCNA, CCSA
**********************

 

[kHz]

Thank you, Chris. Your line:

So the host pluto was added to the master galaxy.org zone file on the primary DNS server, yes? And your local DNS server is mars.galaxy.org, yes?

is correct for both. pluto was added to the master galaxy.org zone file on the primary DNS server. And the local DNS server is mars.galaxy.org.

Since the server pluto doesn't exist in the galaxy.org zone file on mars.galaxy.org (my local server), does that mean the search is going out to galaxy.org and resolving pluto on the primary server out east?

So if I changed master to slave, then the primary server will attempt a zone transfer and it will add the entry for pluto to my local galaxy.org zone file?

Thanks for you help!

 

[ChrisAC]

Firstly, are you absolutely sure that the pluto host isn't in your zone file on Mars? As your server thinks that it's the master for that zone, it shouldn't be checking elsewhere.

Your slave server mars.galaxy.org will only pick up any changes on the galaxy.org zone if it is correctly configured as a slave for that zone and is talking to the master. It will also need a reload (rndc reload or ndc reload depending on BIND version)to make it check the serial number on the master servers zone file.

What would also stop it from pulling the new zone file would be if whoever made the change on the master server, ie. whoever added the new host pluto, didn't update the serial. The slave will check its serial number for the zone and compare it to the serial on the master to see if it needs to pull the updated zone file.

I would suggest that you talk to your guys on the east coast to get your config right.

Good luck.

Chris.

**********************
Chris A.C, CCNA, CCSA
**********************

 

[kHz]

Absolutely positive pluto is not in the zone file on mars.

Thank you very much for your answers. They certainly helped me understand better what is going on. I will check with the guys back east.

Thanks!