DNS with multiple connections -or- how to set "primary" IP?

Question

DNS with multiple connections -or- how to set "primary" IP?

A server that previously had only one purpose (file server) is now serving a second purpose (receiving files over sftp). Because the software that sends the files over sftp can't be changed, I set the second ethernet port on this server to the same settings as the server that was decomissioned. (Same network, different IP)

The hostname of this machine SHOULD be: myservername.something.something.com

The hostname of this machine is being reported as: myservername.local.

That means DNS is broken on this machine, which ***** because it's my OD Master and I can't get clients to bind.

When I run "sudo changeip -checkhostname" I get the followng response:

Primary address = xx.xxx.xx.1

Current HostName = the.correct.host.name

The DNS hostname is not available, please repair DNS and re-run this tool.

The problem is that the IP address listed under "Primary address" isn't the address to which the host name is registered. (Let's say the hostname is registered to xx.xxx.xx.2)

So I either need to set the server's "primary" IP to the correct address, or figure out how to use changeip -checkhostname to check a specific adapter.

dig and dig -x return the correct data for the IP and hostname... the DNS servers are set up correctly.

Any advice on properly setting up DNS on a server with two IP addresses?

Thanks in advance!

Posted on Jul 9, 2013 9:32 AM

Reply

Answer 1

Best reply

MrHoffman

Community+ 2024

Level 10

116,199 points

Jul 9, 2013 11:58 AM in response to Brian Dieckman

If the host name is myservername.local, then DNS services are configured incorrectly. The .local top-level domain is reserved to mDNS (Bonjour) and should not be mixed with DNS (unicast DNS); that mixing usually works, but it's not reliable and not recommended per public statements by some of Apple's networking engineers.

As for selecting the primary address, drag the primary address to the first position in Network Preferences.

DNS itself doesn't care if there are multiple addresses associated with a host. That'll all work fine, so long as the subnet routing is set up correctly.

Reply

Answer 2

Jul 9, 2013 1:03 PM in response to MrHoffman

So setting the "primary" IP of the server did the trick, although I did notice some oddness in my DNS settings.

I removed the existing zones (which were for another computer, not the server I'm working on) and added the zone and machine which appears to have done the trick with regards to OD.

The only thing left that I'm concerned about is the reverse lookup in DNS now has .(null) at the end?

XX.XXX.XX.in-addr.arpa.

xx.xxx.xx.2 Reverse Mapping myservername.mydomain.com.(null)

I'm Googling now, but I haven't found anything obvious... is this familiar/expected?

(If you can't tell, I'm no DNS whiz...)

Thanks again, Mr. Hoffman!

-Brian

[EDIT] Some additional info: now the value in the reverse listing says:

XX.XXX.XX.in-addr.arpa.

xx.xxx.xx.2 Reverse Mapping myservername.mydomain.com.null.xx.xxx.xx.in-adr.arpa.

Wha?

[EDIT AGAIN!] I was able to get the local machine reverse entry to look correct after the following:

1) select the reverse mapping (under reverse zone) and remove

2) select the machine (under primary zone) and remove

3) stop DNS

4) start DNS

5) select the primary zone and add a machine record with the proper IP and machine name

6) click save

7) stop DNS

8) start DNS

I've also added the other severs in my cluster to DNS so I don't have to go to the plant-wide dns server every time I try to connect by name.

Reply

Answer 3

Jul 9, 2013 2:04 PM in response to Brian Dieckman

It might appear that your local DNS configuration is wrong. Here's how to set up OS X Server DNS services. (That was written for Snow Leopard, but the Lion and Mountain Lion setup is basically the same, once you select Show All Records in the DNS configuration section of the Server.app tool.)

If you have plant-wide DNS servers available (such as those that are part of the typical Microsoft Windows Server Active Directory setup), you don't need to run DNS services on your OS X Server box. Simply reference the plant-wide DNS servers.

(Any DNS that's considered "plant-wide" should probably also be "servers"; multiple DNS servers with some primary and secondary servers. FWIW.)

Reply