How to install Big Sur to Mac Mini Late 2012 and other Catalina-capable machines

Update from Nov 22 2020: I updated the guide for a release version of a Big Sur! Now it uses some new tools made by community, that makes process a lot easier in many ways. The information provided below was confirmed to be valid on a 11.0.1.

Update from Feb 28 2021: I’ve successfully updated my 11.0.1 installation to 11.2.1 and added information about updates.

With the new release of Big Sur, apple have dropped my “brand new” Mac Mini Late 2012, so that’s how I made it work with the help of MacRumors community.

Grab a 16GB USB drive

To install Big Sur, you’ll need an USB drive of at least 16GB in capacity.

Make a Time Machine backup

As always, before installing a new major release of any macOS, you should do a TM backup, especially before installing a Big Sur, which changes TM backups in some ways.

Create separate volume

Please, don’t install it as a single OS. If you have a working OS on your machine, please KEEP IT. Run Disk Utility and create new partition, at least 60 GB in size.

Important: it must be not in the same container as your current mac installation. Installing Big Sur in the same APFS container as your current macOS installation will cause issues. Create separate Partition, not just Volume.

Create installation USB

  1. Open Disk Utility

All data on the USB drive will be destroyed in this process!

Downloading installer

Versions that proven to be working for me:

  • 11.0.1 (initial install)

Warning! Before trying to install anything newer than 11.2.1, please make sure that it’s still supported by micropatcher! There are some troubles in installing 11.3 Beta 2, which was not resolved at the time of writing this guide. 11.2.1 is your best bet for now (as of Feb 28 2021).

If you have supported mac around, you can just download Big Sur installer from the MAS.

Otherwise, follow this guide:

For downloading Big Sur installer, we will use a tool called gibMacOS

  1. Open this link, and press green “Code” button, and download as zip

Source: https://dortania.github.io/OpenCore-Install-Guide/extras/big-sur/#grabbing-the-installer, macrumors forum

Creating Installer USB

Open terminal and do this:

sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia --volume /Volumes/Your\ Usb\ Volume\ Name

Patching installer and installation

For further steps, look at the big-sur-micropatcher’s README:

There is seemingly a lot of steps, but you can start right from the step 6, and ignore steps 12, 16, 18 and 19 if installing on the Mac Mini 2012.

It’s already very detailed and there is no need to copy-paste it here :)

After all these steps, you should have perfectly working Big Sur installation with WIFI and etc.

Updating macOS

For now, OTA updates are not supported for this installations. However, there is a way of updating Big Sur installations using full installer.

The steps are:

  • Make sure that desired version is still supported by micropatcher

Consider subscribing me on twitter: https://twitter.com/libneko

There will be little to no macOS-related stuff, but I will be very pleased if you do so :)

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