What version of Mac OS is installed on your recovery partition?

Long ago, when cats ruled the Mac and OS X Lion was king, Apple began including a hidden partition on the Mac’s boot device. Known as the Recovery HD, it was a special partition that could be used to troubleshoot a Mac, fix common startup problems, or worst case scenario, reinstall OS X.

Pretty nifty, though nothing really new; competing computer systems offered similar capabilities. But one thing that set Mac Recovery HD apart from the rest was that the operating system was installed over the Internet, downloading a fresh install of OS X when needed.

Which brings us to the questions we are going to answer in this article.

What version of OS X is actually installed on my recovery hard drive?

It’s not a bad question. It seems obvious at first. If you just bought a new Mac, it will have the latest version of OS X installed, and that’s what HD Recovery will be linked to. But what about those of us who didn’t buy a new Mac and just upgraded from earlier versions of OS X?

If you upgraded from Snow Leopard (OS X 10.6) to Lion (OS X 10.7), your new Recovery HD partition will be linked to the Lion version of OS X. Simple enough, but what if you later upgrade to Mountain Lion (OS X 10.8 ), or if you skip to Mavericks (OS X 10.9) or Yosemite (OS X 10.10)? Is the Recovery HD volume upgraded to the latest OS, or if I were to use the Recovery HD partition to reinstall OS X, would I get back to OS X Lion (or whatever version of OS X you started with)?

The simple answer is that whenever you do a major OS X upgrade, the Recovery HD partition is also upgraded to the same version of OS X. So an upgrade from Lion to Mountain Lion will result in a recovery from HD. linked to OS X Mountain Lion. Similarly, if you skipped some versions and upgraded to OS X Yosemite, the Recovery HD partition will reflect the change and will be linked to OS X Yosemite.

Pretty straightforward, at least so far. This is where it gets difficult.

What happens when I have multiple copies of HD recovery?

If you’ve been reading about troubleshooting your Mac here on Lifewire, then you know that one of our recommendations is to install a copy of Recovery HD on a second, or even third, bootable storage device. This can be a second internal drive, for Macs that support multiple drives, an external drive, or even a USB flash drive.

The idea is simple: you can’t have too many recovery HD volumes up and running, in case you need to use them. This will become painfully obvious when you encounter startup problems with your Mac’s drive, only to find that the Recovery HD doesn’t work either, since it’s part of the startup drive itself.

So now you have multiple Recovery HD partitions on multiple boot volumes. Which one do you use, and how can you tell which version of Mac OS will be installed in case you need to reinstall the operating system? Read on to find out.

How to identify the version of Mac OS linked to a recovery hard drive

By far the easiest way to find out which version of the Mac operating system is linked to a Recovery HD partition is to restart the Mac using the startup manager.

Plug in any external drive or USB flash drive that contains a Recovery HD partition, then hold down the options key while turning on or restarting your Mac (see Mac OS X startup keyboard shortcuts for more information). This will bring up the startup manager, which will display all startup devices connected to your Mac, including recovery HD partitions.

Recovery HD partitions will display as Recovery-xx.xx.xx.xx, where xx is replaced by the Mac OS version number associated with the Recovery HD partition. For example, when we use the bootloader we see the following:

CaseyTNG Recovery-10.13.2 Recovery-10.12.6 Recovery-10.11

There are other boot devices on our list, but CaseyTNG is our current boot drive, and from the three Recovery HD partitions, each showing the associated Mac OS version, we can easily select the Recovery HD partition we want. use.

By the way, it’s best to use the Recovery HD partition that is associated with the version of OS X that is running on the bootable media that is having problems. If that is not possible, you should use the closest match available to you.