Erase install

[Alwyn]

Last time I restored my previous 2010 iMac I had the original disks for Snow Leopard. I will shortly be selling my 2014 iMac. I have read the various Apple instructions. What I am not clear about is how I install the Mac OS. I have Catalina but don't know how to back it up without backing everything else up.

 

[ferrarr]

Did you see this,

https://support.apple.com/en-us/HT201065

You should have a Recovery partition, which will erase the iMacs drive, and install a cleaned version of Catalina.

 

[Alwyn]

Did you see this,

https://support.apple.com/en-us/HT201065

You should have a Recovery partition, which will erase the iMacs drive, and install a cleaned version of Catalina.

Yes I have read it and saved a copy. It was the Recovery partition that concerned me. Is that partition standard or do I have to partition the drive myself?

 

[MacInWin]

The recovery partition should have been created by the installation process for macOS as you upgraded to Catalina. To see if it is actually there, boot while holding Option key and see if the Recovery partition is listed as one of the options from which to boot.

 

[Alwyn]

Thanks. I tried the option key (marked cmd with a square with curly corners on my keyboard) by itself to no effect. I then tried the cmd with the letter R are and the attached screenshot is what came up. Disk utility showed the file marked sys_util. Clicking on partition produced the 3rd image.

 

[MacInWin]

option key (marked cmd with a square with curly corners on my keyboard)

I think that is the Command key, not the Option key. Try again with the Option key. On my keyboard it is labelled option and alt in the corner. It also could have this symbol:

• Option (or Alt) ⌥

As for the displays, the first is the Recovery boot options for things you can do in Recovery. The second, of Disk Utility is sort of useful, but to really see what is going on, on the View button, select "Show All Devices." The two Volumes you can see on the hard drive are the system volume (Colin's iMac) and the user volume (Colin's iMac - Data). You don't want to mess with them as the third panel warns. Apple's newest drive format is APFS and instead of partitions it has Containers and in the Containers are Volumes. Those are what you are seeing. If you select "Show All Devices" the drive itself will appear and the Container for those two Volumes will also appear. The note is saying that the OS now manages drive space for you so that all the Volumes share the remaining space in the Container dynamically. No more resizing partitions, each Volume gets what it needs until the drive is full.

So, try the Option key again and see what you get.

 

[Alwyn]

Thanks; that worked but this is what I got and there doesn't seem to be any partition.

 

[MacInWin]

Ok, so no Recovery Volume on the drive, just the one. Given that you plan to get rid of the device, I would suggest a full backup (TM will do, and it's free) to an external drive. Check out the backup to be sure you have everything you wanted. Once you are confident you have your files safe, follow the steps given in the document in Post #3. Step seven has links to how to do an internet reinstall of the OS, which will allow you to erase the entire drive to get rid of your data and put a clean version of macOS on it for the buyer. Follow all the steps in the Apple document to get the Mac off your account and out of iCloud so that the new owners will be able to start from scratch and your stuff is secure.

 

[Alwyn]

Thanks Jake. I have CCC as well as backups to my Time Capsule and also less frequently to Time Machine so am not worried about being unable to restore to the new machine. I will do that before erasing the drive on the current machine. My concern all along has been that the buyer will be able to use it. Your help has been invaluable. I hope to be able to add to your score although I can't yet see an option to do that! Colin.

 

[MacInWin]

Colin, I don't do this for score, but thanks for the thought. I just like to see folks get the max out of their Mac.

 

[IWT]

@Colin,

That "score" thing - that's his age! Not many people know that

Ian

 

[Alwyn]

@Colin,

That "score" thing - that's his age! Not many people know that

Ian

Only goes to show that wisdom comes with age! Happy New Year to all & sundry.