skylarking

Q: Guhhh! I just killed my Mac Pro with a terminal entry!

Ok Im an idiot. I have a 2007 Mac Pro 2,1.


I was trying to get some 64 kernel stuff to work and I entered a command I found.


I then restarted my Mac pro and am getting the No Entry sign then the machine starts up.


I can see the drives fine on my laptop via Target disc mode.


Here is the link to the thread

https://discussions.apple.com/thread...art=0&tstart=0


Here is the code

sudo systemsetup -setkernelbootarchitecture x86_64


Help please

Mac Pro, Mac OS X (10.7.3), 3 GHz Quad-Core Intel Xeon

Posted on Jun 25, 2012 4:06 AM

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Q: Guhhh! I just killed my Mac Pro with a terminal entry!

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  • by skylarking,

    skylarking skylarking Jun 25, 2012 4:11 AM in response to skylarking
    Level 1 (0 points)
    Jun 25, 2012 4:11 AM in response to skylarking

    I can't even get the machine to start up via a USB Lion pressing the C key. Or Shift or S.

  • by skylarking,

    skylarking skylarking Jun 25, 2012 4:35 AM in response to skylarking
    Level 1 (0 points)
    Jun 25, 2012 4:35 AM in response to skylarking

    ok so I have removed the start up hard drive and the machine strts up fine with the Lion USB.

     

    Ill just clean the drive and hope for the best.

  • by The hatter,Solvedanswer

    The hatter The hatter Jun 25, 2012 5:50 AM in response to skylarking
    Level 9 (60,935 points)
    Jun 25, 2012 5:50 AM in response to skylarking

    Did you try a simple pram zap to clear ?

     

    With 32-bit firmware, you cannot boot into 64-bit kernel; it’s not possible.

    bits

    To determine if your Mac has 32-bit or 64-bit firmware, copy/paste the following command shown in red into Terminal (Terminal is found in the /Applications/Utilities folder):

    llcMP:~ lloyd$ ioreg -l -p IODeviceTree | grep firmware-abi  | |   "firmware-abi" = <"EFI64">  

     

     

    Even if you cannot or do not boot the Mac OS X Snow Leopard kernel into 64-bit mode, you can run your 64-bit apps as 64-bit, and they can take advantage of all the memory in the machine.

     

    Apple has added a command line setting for enabling the 64-bit kernel. You can open a Terminal window and type: 

    sudo systemsetup -setkernelbootarchitecture x86_64

    This is the method I use, because I can leave it set the way I want to; having to hold down '6' and '4' keys at startup is absurd, it’s ridiculous that Apple did not provide a system preference panel for this.

    The change is shown in red below (“arch=x86_64”). Use a plain-text editor, such as Text Wrangler.

    Edit the file:

    /Library/Preferences/SystemConfiguration/com.apple.Boot.plist

    Insert arch=x86_64 into the Kernel Flags field.

    <?xml version="1.0" encoding="UTF-8"?>  <!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">  <plist version="1.0">  <dict>  <key>Kernel</key>  <string>mach_kernel</string>  <key>Kernel Flags</key>  <string>arch=x86_64</string>  </dict>  </plist>  

     

    The PRAM method for always booting into 64-bit mode PERMALINK 

     

    I’m not a big fan of this method, because I’d rather edit a text file than mess with non-volatile machine settings in the computer itself. This method sets the PRAM (parameter RAM) to tell the machine to boot 64-bi modet. It’s unclear what happens if this is done on a machine that is not 64-bit capable, or if the com.apple.Boot.plist method interacts with it (which overrides which?).

     

    • It forces the Mac to always try to boot into 64 bit mode (assuming the boot volume contains a 64 bit kernel).

     

    It can be undone by resetting the PRAM by booting up while holding down the <command>, <option>, 'P' and 'R' keys.

     

    I have not tested this method, you’re on your own here. Open a Terminal window and enter this command:

    sudo nvram boot-args="arch=x86_64"

    You should be able to reset things as follows:

    sudo nvram boot-args=""

    Again, I have not tested this.

     

     

    http://macperformanceguide.com/SnowLeopard-64bit.html

  • by skylarking,

    skylarking skylarking Jun 25, 2012 7:49 AM in response to The hatter
    Level 1 (0 points)
    Jun 25, 2012 7:49 AM in response to The hatter

    Hatter, you always give me more than what I would expect.

     

    I thank you for this. I will now sit down and try to decifer all the info you have given me.

     

    Panic is over as I have the machine up and running, I should come clean that I was trying to install Mountain Lion via opening the enlcosed package whilst I was entering the code above.

     

    Thanks again for all your help.

     

    I have run what you have said and I am  "firmware-abi" = <"EFI32">