Back-up Hard Drive 1 T half for El Capitan

[Patth9]

I have an older Mac Mini that has Snow Leopard on it which I would like to keep.

Is it possible to install El Capitan onto 1/2 of a TB Hard Drive (backup), and then boot up in the El Capitan side of the TB Hard Drive and use it that way.

Hope someone can understand this question.

Patt

 

[MacUser2525]

Yes use Disk Utility to split the hard drive name it was you like for the El partition then once you start the install choose it (new partition) as the install target let it do its thing. Holding the option key when starting allows you the choice of which volume to boot the old OS or the new or you use the Startup Disk option in the system preferences to reboot into which every OS you wish.

 

[Fishrrman]

You'll need to partition the internal drive using Disk Utility.

You should be able to do this while booted from Snow Leopard.
It depends on how "scattered around" your files are, and how much space you've used up already.

It might be necessary to defrag the drive before you attempt to partition. This will group all the files "at the head end" of the existing (single) partition, leaving "the rear" free to split off.

If you're having problems, another way is to:
1. Use CarbonCopyCloner to create a cloned copy of the existing drive on an EXTERNAL drive.
2. Boot from the cloned copy.
3. Re-initialize the internal and partition
4. Use CCC to restore from the cloned copy.
5. Now install El Capitan onto the second partition.

 

[Patth9]

Thank you, MacUser2525 and
Fishrrman,

I use CCC. I haven't been on this (one and only) site for a long time; I needed these refreshing reminders. Thank YOU!

It's folks like you two that keep me up and running. I started using a Mac in 1995 and now, 21 years later at 71, you all are still here helping.
https://forums.macrumors.com/members/macuser2525.101545/