need to restart mDNSResponder after every boot up

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Level 1

8 points

need to restart mDNSResponder after every boot up

I have had a problem about name resolution on my mac(running on 10.6.8) from yesterday.

After a reboot yesterday, suddenly I coudn't use safari so I investigated some.
nslookup worked correctly, but ping didn't. seemed mDNSResponder had the problem.
I found mDNSResponder process on my process list by using ps command then I tried restarting the service with following commands.

$ sudo launchctl unload /System/Library/LaunchDaemons/com.apple.mDNSResponder.plist $ sudo launchctl load -F /System/Library/LaunchDaemons/com.apple.mDNSResponder.plist

Yes, this solved the problem at the moment BUT I need to restart the service after every boot up. I don't know why first invoked process doesn't work correctly.

Any Idea?

Thanks!

MacBook Air, Mac OS X (10.6.8)

Posted on Nov 22, 2011 12:14 AM

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Answer 1

Nov 22, 2011 8:33 AM in response to Juske

Check your logs ( Applications > Utilities > Console.app) for any relevant error messages.

Try aiming your box at different DNS servers. If you're running Mac OS X client as I suspect (and are not running Mac OS X Server and its DNS server capabilities), then (as a test) select the Google DNS server at 8.8.8.8 (only; list no other DNS servers in System Preferences > Network of DNS server hosts listing) as your designated DNS server, and see if the box starts working after reboots.

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Answer 2

Juske Author

Level 1

8 points

Nov 23, 2011 4:59 PM in response to MrHoffman

Thanks for the advice!

But unfortunately, It didn't worked.

Still need to restart mDNSResponder manually.

There is a line that mDNSResponder started on my console-log.

so It seems mDNSResponder is working but not functional to name resolution.

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Answer 3

Nov 23, 2011 5:25 PM in response to Juske

How many DNS servers do you have listed in your Network Preferences?

And which DNS servers are listed? Those of your ISP? Any private, local DNS servers?

I was going to suggest reloading the 10.6.8 combo update, but that doesn't line up with your symptoms.

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Answer 4

Juske Author

Level 1

8 points

Nov 23, 2011 5:39 PM in response to MrHoffman

2 servers are listed on DNS tab in network preferences and It works from the other machines.

So I think It's not a server problem.

How can I reloading the update? might worth trying it anyway.

Thanks!

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Answer 5

Nov 24, 2011 1:28 PM in response to Juske

Humor me. (I'm wondering if you have a bad or buggy DNS server.) Are these two DNS servers you have listed your ISP DNS servers?

And to confirm, did you remove both of those servers from this host as a test, and replace them with just one DNS server entry with just the 8.8.8.8 Google DNS server, and test operations after a reboot?

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Answer 6

Juske Author

Level 1

8 points

Nov 24, 2011 6:15 PM in response to MrHoffman

Unfortunately, It didn't work 😟

It's local DNS servers but nothing good happens when I changed those to ISP's or google's.

Hmm, seems I have to re-install whole OS.

Thanks for the advices!!

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Answer 7

Nov 25, 2011 7:31 AM in response to Juske

I'd be taking a careful look at those local DNS servers, as DNS errors in the local servers are not particularly rare, and these errors can easily derail the environment. A failed or buggy local DNS server would also line up with the observed misbehavior, too.

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Answer 8

Oct 4, 2012 10:57 PM in response to Juske

Did you ever get this resolved? I am having the exact same issue. I thought it might be a permission issue, but repairing permisssion does not help.

dave

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Answer 9

Proto

Level 1

120 points

Oct 15, 2012 2:07 PM in response to dnasralla

Same here - I recently had the logic board replaced and since then, mDNSResponder seems to start "empty" with each boot.

I too have to sudo unload/load it after each boot in order to get it going.

Or could it be a hardware problem after all?

Cheers,

Steve

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Answer 10

Oct 15, 2012 3:11 PM in response to Proto

Hey Steve,

I doubt it is a hardware issue. I didn't have time to troubleshoot more, so I just reinstalled the OS (did NOT wipe the drive). My OS was 10.6. Haven't had issues since.

HTH,

dave

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Answer 11

Juske Author

Level 1

8 points

Oct 15, 2012 6:22 PM in response to dnasralla

I reinstalled the OS and it works well now.

I believe there is a way to fix it without reinstalling the OS but it would take so much time to investigate.

Thanks,

J

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Answer 12

Oct 15, 2012 8:38 PM in response to Juske

Exactly. Glad it's working now.

dave

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