Problems with mDNSResponder in Lion?

Discussion in 'macOS' started by miniConvert, Nov 21, 2011.

  1. miniConvert macrumors 68040

    miniConvert

    Joined:
    Mar 4, 2006
    Location:
    Kent, UK - the 'Garden of England'.
    #1
    Anyone else having DNS problems in Lion?

    Things like forums.macrumors.com frequently break for me, where macrumors.com works fine, until I kill mDNSResponder - where it instantly starts working again.

    I've tried switching DNS servers to no avail and am currently using Google 8.8.8.8 & 8.8.4.4.

    A colleague who also just upgraded to Lion is getting the same thing on a number of websites.

    Is it a bug or perhaps something that went wrong with the upgrade? Any advice greatly appreciated!
     
  2. miniConvert thread starter macrumors 68040

    miniConvert

    Joined:
    Mar 4, 2006
    Location:
    Kent, UK - the 'Garden of England'.
    #2
    Bump?

    The affected machines are all upgraded from Snow Leopard if that helps. New MBP arrives this week with Lion factory-installed, it'll be interesting to see if that's any better.
     
  3. Mr. Retrofire macrumors 601

    Mr. Retrofire

    Joined:
    Mar 2, 2010
    Location:
    www.emiliana.cl/en
    #3
    It seems to be a problem with Safari v5.1.0 or higher in SL. Safari < v5.1.0 does not have this problem.

    I've the same problem (no available DNS) with books.google.com and ***.youtube.com. Probably a WebKit2 problem.

    If possible, use Firefox.
     
  4. miniConvert thread starter macrumors 68040

    miniConvert

    Joined:
    Mar 4, 2006
    Location:
    Kent, UK - the 'Garden of England'.
    #4
    Hi,

    Just to come back to this, it's still a problem. Frequently affects forums.macrumors.com and a few other sites I use, while others never tend to be affected.

    It's not a browser issue as Firefox has the same problem as Safari has. If I start a ping to forums.macrumors.com nothing happens (it's waiting for the lookup) until I open a new terminal and do sudo killall -9 mDNSResponder, at which point it springs into life.

    Same if I'm browsing - if I'm trying to get to a site, or I'm on a site but images, for example, aren't loading because they're on a different hostname, I do sudo killall -9 mDNSResponder in Terminal and instantly everything kicks in.

    I can reproduce it on my iMac at work and MacBook Air at home, both upgraded from Snow Leopard to Lion.

    It doesn't happen on my new MacBook Pro, which had Lion preinstalled.

    Driving me INSANE. Any ideas?
     
  5. isma macrumors newbie

    Joined:
    Aug 24, 2011
    #5

    Yesterday I had my computer at 95º with some cores at 100% because mDNSResponder was doing something. I did shutdown all running apps and nothing worked until I restarted my macbook air. As all was working fine, I left my laptop on sleep mode. Today when I have come home, my computer was very hot at 95º with the same process mDNSResponder at 100%. Anybody knows what is happening with this process ?

    Now I do not trust my computer in sleep mode.


    The errors that I get are

    05/03/12 17:56:51,026 mDNSResponder: ERROR: accept: 24 (Too many open files)
    05/03/12 17:56:51,026 mDNSResponder: ERROR: accept: 24 (Too many open files)
    05/03/12 17:56:51,026 mDNSResponder: ERROR: accept: 24 (Too many open files)
    05/03/12 17:56:51,026 mDNSResponder: ERROR: accept: 24 (Too many open files)
    05/03/12 17:56:51,026 mDNSResponder: ERROR: accept: 24 (Too many open files)
    05/03/12 17:56:51,026 mDNSResponder: ERROR: accept: 24 (Too many open files)
    05/03/12 17:56:51,026 mDNSResponder: ERROR: accept: 24 (Too many open files)
    05/03/12 17:56:51,026 mDNSResponder: ERROR: accept: 24 (Too many open files)
    05/03/12 17:56:51,026 mDNSResponder: ERROR: accept: 24 (Too many open files)
    05/03/12 17:56:51,026 mDNSResponder: ERROR: accept: 24 (Too many open files)
    05/03/12 17:56:51,026 mDNSResponder: ERROR: accept: 24 (Too many open files)
    05/03/12 17:56:51,026 mDNSResponder: ERROR: accept: 24 (Too many open files)


    The only solution is to restart, but I do not know what is causing this problem. Any idea ?
     
  6. miniConvert thread starter macrumors 68040

    miniConvert

    Joined:
    Mar 4, 2006
    Location:
    Kent, UK - the 'Garden of England'.
    #6
    Too many open files? That doesn't sound good.

    Could anything on your machine be performing a high volume of DNS lookups? Perhaps some sort of peer to peer application/sharing service/torrent type app?

    You may have to resort to backing up and reinstalling the OS.

    Btw, this is different to the issue I was describing, where mDNSResponder doesn't seem to be working properly for lookups.
     

Share This Page