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Barnum

macrumors newbie
Original poster
Sep 4, 2008
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I’ve sent my old iMac to a computer repair shop (I’m not sure if it’s Apple authorized) to have my malfunctioning hard drive replaced with a new one. My question is how do install os x (El Capitan) onto the new drive? I don’t have an installation disc but I do have a Time Machine backup drive.
 
I'm not sure if I will be able to do that on my iMac. It's a late 2009 Core 2 duo model.
 
Your 2009 iMac is too old for internet recovery.
Your Time Machine backup (from El Capitan) SHOULD be bootable, and you would then be able to restore your backup on the replacement hard drive.
A better plan would be to create a bootable flash drive with the El Cap installer. Very easy to do if you can download that installer on another Mac.
Then, you can install El Cap fresh on your new drive, and the restore of the Time Machine backup will be even easier.
 
I’ve sent my old iMac to a computer repair shop (I’m not sure if it’s Apple authorized) to have my malfunctioning hard drive replaced with a new one. My question is how do install os x (El Capitan) onto the new drive? I don’t have an installation disc but I do have a Time Machine backup drive.
If the TM backup was to a local disk like USB, then just attach it and option key boot to it. That will take you to a recovery screen. From there use Disk Utility to erase the internal drive to Mac OS Extended (Journaled). Then quit Disk Utility and click restore OS X at the top.
 
My understanding is that Time Machine backups are not bootable. Has this changed recently?
[doublepost=1466874399][/doublepost]Your Mac should have shipped with a Restore/Install DVD. Do you still have it? If so, you can boot from it by holding down Command-C. Then use disk utility to format the new drive as Apple Extended Format (Journalled). Then install the OS from the DVD. On reboot, the computer should ask you if you want to transfer data from an older Mac. At that point, connect your Time Machine backup drive and select it. This should copy over all your old files, apps and preferences.

Once you are done, go to the App Store and download and install a fresh copy of El Capitan. This will cause the installer to create a recovery partition. Then run Software Update to update all your software.
 
My understanding is that Time Machine backups are not bootable. Has this changed recently?

You can't boot and run the Mac, but like CoastalOR mentioned, since 10.7.2 you can boot to the recovery partition on the TM backup disk.
 
Learn something new every day! I presume that works only if the Time Machine backup is to a USB drive, not to a Time Capsule?
 
A Time Machine backup of OS 10.7.2 and later is bootable to the OS X Recovery that is part of the Time Machine backup.
http://pondini.org/OSX/RecoveryHD.html
I think this no longer works with El Capitan...

The solution is to manually edit the com.apple.Boot.plist file (Backups.backupdb/.RecoverySets/0/com.apple.recovery.boot/com.apple.Boot.plist)

Replace :
<string>\Backups.backupdb\.RecoverySets\0\com.apple.recovery.boot\kernelcache</string>

With :
<string>\Backups.backupdb\.RecoverySets\0\com.apple.recovery.boot\prelinkedkernel</string>

Here in French, sorry I am not able to translate this in English.
http://forums.macg.co/threads/booter-sur-sauvegarde-tm.1272471/#post-12977415

EDIT : just tested myself, it does work : the Time Machine backup is bootable again after editing the .plist file.

Path on my TM backup : Backups.backupdb/.RecoverySets/1/com.apple.recovery.boot/com.apple.Boot.plist

.RecoverySets
is an hidden folder, thus you need to reveal the hidden items in Finder before editing the plist file.
 
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Hmm. Pondini doesn't mention El Capitan, and I think he died before it was released. But he does mention a problem with USB3.
 
Learn something new every day! I presume that works only if the Time Machine backup is to a USB drive, not to a Time Capsule?

Correct... it needs to be a locally attached backup like USB, FW, or TB.

I think this no longer works with El Capitan...

The solution is to manually edit the com.apple.Boot.plist file (Backups.backupdb/.RecoverySets/0/com.apple.recovery.boot/com.apple.Boot.plist)

Well crap. Nice find and the first I heard this is borked. Why the heck would Apple do this. Maybe they are thinking all the newer machines can restore from Internet recovery so they don't need this I suppose... but still. :mad:

That workaround is not going to help if you don't have a bootable system to start with to edit the plist file from.
 
Welp, I got my computer back & I chickened out and made an appointment with the Genius Bar and lugged the 30 pound beast to the nearest Mac Store. El Capitan is now installed and now all I have to do is wait 7 hours to load all my files and apps to my hard drive. Yay USB 2.0!
 
Well crap. Nice find and the first I heard this is borked. Why the heck would Apple do this. Maybe they are thinking all the newer machines can restore from Internet recovery so they don't need this I suppose... but still. :mad:
Fixed by Apple in macOS Sierra : kernelcache replaced with prelinkedkernel.

Also : the Recovery partition of El Capitan was updated through the Mac App Store on June 23rd or 24th.

May be the TM backup is bootable again with El Capitan ?
I can not test myself because I had manually edited the .plist file (post #10).
 
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Fixed by Apple in macOS Sierra : kernelcache replaced with prelinkedkernel.

Also : the Recovery partition of El Capitan was updated through the Mac App Store on June 23rd or 24th.

May be the TM backup is bootable again with El Capitan ?
I can not test myself because I had manually edited the .plist file (post #10).

Does not appear so. I just downloaded the full installer and reinstalled El Capitan and although that plist shows it was created today along with my install, it still shows kernelcache in that section.
 
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I'm confused...

Time Machine (El Capitan) based does not allow to boot from recovery partition on Time Machine drive?
 
Hmm,
I can still boot with El Capitan installer on USB (flash drive), and choose restore from TM, correct?

Which version of El Capitan broke it? Since 10.11. (zero)?

That's such a fundamental flaw. wow
 
Hmm,
I can still boot with El Capitan installer on USB (flash drive), and choose restore from TM, correct?

Which version of El Capitan broke it? Since 10.11. (zero)?

That's such a fundamental flaw. wow

Yes... you could still boot either from a USB key or Internet recovery on newer Macs that support it, then restore.

I don't know which version broke this.

Maybe with the (long) countdown to booting from APFS, Apple decided to no longer maintain the feature.

I don't think so, because Bruno09 reports it is back in Sierra. So maybe just an oversight.
 
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