DNS error - "requires at least one Nameserver"

I saw similar behavior recently on one server I was working on. (This was with the 10.6.7 and associated server tools; haven't been down this path with 10.6.8 and the updated server tools.)

If what I saw is similar to what you're seeing here, then try this...

First, if you don't have a recent backup copy of your boot disk that you trust and are willing to use, then back up your boot disk before you proceed by booting a distribution disk and using Disk Utility to make a full copy of your boot disk to external storage. This backup is your path back to operations if Badness Happens.

Once you have rebooted your system from your backup, stop DNS services and exit Server Admin, if either or both are running.

Then launch Terminal.app, and navigate into and delete or rename the Server Admin properties list file:

~/Library/Preferences/com.apple.ServerAdmin.plist

Then relaunch Server Admin, and you should be able to fix your DNS services.

This is your local copy of the preferences file for Server Admin, not a system-wide preferences.

The "immutable" DNS settings were (after digging around) being recovered from the plist file. (I've also had rare occasion to edit that plist file, when things go Really Wonky, and to change the immutable settings to some other temporary domain name, which then let me Get On With It All with the intended domain name.)

Um, and without intending any disrespect, why would I tell you to alter your backup? That is, after all, your backup, and is your path back to operations should your primary drive suffer a corruption due to changes made here.

The plist is built and rebuilt per user; it's in a per-user directory area and not in a system-wide area, too.

And should things go seriously weird, well, that's why you have that backup.

On thinking about it, I did end up editing the plist the last time I hit this case. I changed the errant old domain in the plist - the unkillable zombie domain - to another domain name, and then let Server Admin rebuild that, added what I needed (under the correct domain name) and then deleted the zombie that had been reanimated from the plist. That plist editing is feasible via TextWrangler or various other plist-capable tools, or with Xcode or other means, depending on your level of comfort with the command line. This is definitely not my preferred approach, but it worked.

Actually, backing up to a backup and then booting from it is a good idea because if it doesn't work all you have to do is boot from the internal drive. No copying back to. I had this same problem and I can't remember how I fixed it but I tried deleting entries and they would come back, once I had double entries. For the nameserver error after you enter the information in for the primary, a record and anything else, go to the reverse zone and see if entering the nameserver there helps for me it did for that, but then everything would disappear when I would save. I used changeip old ip new ip old host new host once flushing the dns cache and using scutil but an apple rep said that was a dated technique.

The DNS cache flush is (officially?) triggered by tossing a HUP signal at DNS, though that sequence not what I'd consider particularly well-documented. (It's definitely listedin the source code, if you're inclined to dig for it.)

sudo killall -HUP mDNSResponder

Hi

". . . using scutil but an apple rep said that was a dated technique?"

The Apple Rep is wrong and should not have said this for a number of reasons. Here is a recent thread - there are many more - where Apple Server Support contradict neatly what the Rep has said:

https://discussions.apple.com/thread/2775967?answerId=15530693022#15530693022

HTH?

Tony

It wasn't scutil that he was referring to, it was changeip. Changeip is listed in the documentation as what you are supposed to use to change the ip or hostname of the server as it adjusts settings for all other servers but he said something like entries should be deleted and re-created in dns, I think maybe preferences thrown away and then the changes or each server updated manually. He was a supervisor to the people providing support and he said he kept telling people to tell people to do it the way he said but they usually didn't

Hello jeffmr

That makes more sense as Apple changed the way changeip works anyway. In 10.6 it does not function the same way it did previously. Besides using the command in the past was never a guarantee it would 'fix' DNS or LDAP issues related to DNS. In my experience it did not really work without further work - usually involving a demotion and re-promotion. I stopped using it when 10.5 was released and used other methods instead.

HTH?

Tony