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Karatehero
May 12, 2011, 05:52 PM
I have a mac server setup doing mail and some sharing. It acts also as the primary DNS server for this setup. I didn't originally set this up, but there is only 1 DNS record that I see in the server with a PTR record

2.1.1.10.in-addr.arpa. Reverse Zone -
10.1.1.2 Reverse Mapping servername.domain.com.
servername.domain.com. Primary Zone -
servername.domain.com. Machine 10.1.1.2

Thats my attempt at showing what server manager in DNS is showing. It would appear there is one A record for the server and a PTR record to match. Makes sense.

I want to add a record for another server. I want newserver or newserver.domain.com to resolve to 10.1.1.6. So, I added an A record and put in
newserver.domain.com.
and an IP of 10.1.1.6

In turn it addes an A record, but it adds a new PTR record so my entries now look like:

1.1.10.in-addr.arpa. Reverse Zone -
10.1.1.6 Reverse Mapping newserver.domain.com.
2.1.1.10.in-addr.arpa. Reverse Zone -
10.1.1.2 Reverse Mapping servername.domain.com.
servername.domain.com. Primary Zone -
servername.domain.com. Machine 10.1.1.2
newserver.domain.com. Machine 10.1.1.6

I'm questioning if this is right? I thought this would be an easy process, am I doing something wrong? When I ping 10.1.1.6 it doesn't resolve the name and when I ping newserver or newserver.domain.com I get back unresolved messages.

Any help would be super appreciated!!!!!!!



Karatehero
May 13, 2011, 07:26 AM
I did some more research and I think the problem is that my PTR record for my DNS server starts with 2.1.1.10. Shouldn't it be 1.1.10?

Can I delete the A record for the DNS server without killing AD and OD?

talmy
May 13, 2011, 12:45 PM
Looking at my setup managed through Server Admin (this is Snow Leopard Server). I was told never to touch the reverse DNS entries and that they are created automatically from the forward DNS entries.

That said, my zone (which is local to the LAN) is almy.almy0. (note the period at the end). The nameserver is 192.168.1.6. Note that this creates a reverse zone 1.168.192.in-addr.arpa. So you are right about the fourth digit group not belonging. I've got four machine (A) records set up. Adding and removing these has no effect on OD, at least providing the server's A record is present.

Karatehero
May 17, 2011, 10:18 AM
Just to let you know, I had to nuke my primary zones and readd them. Luckily it didn't kill anything above it but it was a bit nerve racking for a while.

thanks for the help!!!!

jared_kipe
May 17, 2011, 10:50 PM
When you say ping, have you tried just the simple "host domain.com localhost"?

dyn
May 19, 2011, 07:25 AM
Make sure you always flush your dns cache (on the client) before testing anything. This will help prevent strange dns problems while in fact everything is set up correctly.