Does anyone know of a way to install an older version of OS X on a different partition in 10.12?

[monkeybagel]

I have a Mac Pro 5,1, and I am aware of the ./createinstallmedia to create a USB bootable drive, but does anyone know of a way to force the installer for El Capitan or another build of OS X to launch from 10.12 to be able to select another drive or partition to install to? I imagine if SIP was disabled one could edit the OS X version file and change it to 10.11 to fool the installer, but that is a little too much trouble and could be problematic. Anyone have any other ideas?

I actually tried the ./createinstallmedia and it failed after erasing the USB drive, in 10.12 but worked on another Macintosh running 10.11, telling me there is no problem with the drive.

 

[CoastalOR]

Try using Diskmaker X to create a bootable USB installer with El Capitan on it. It has worked well for me, but then I have also had good luck with createinstallmedia.

Was this the Terminal code that you used (assuming the USB stick would have to be named Untitled)?

sudo /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled --applicationpath /Applications/Install\ OS\ X\ El\ Capitan.app --nointeraction

 

[monkeybagel]

Try using Diskmaker X to create a bootable USB installer with El Capitan on it. It has worked well for me, but then I have also had good luck with createinstallmedia.

Was this the Terminal code that you used (assuming the USB stick would have to be named Untitled)?

sudo /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled --applicationpath /Applications/Install\ OS\ X\ El\ Capitan.app --nointeraction

Yes it was. I have used that command many times in the past with no issues, but I don't recall attempting to use it from a newer .1 build of OS X to create install media for a -.1 build.