We had tried a few years ago to get some ancient MacBooks up and running with various Linux distros. But our particular model had challenging WiFi hardware which made it impractical.
I recently took another shot at reinvigorating our Early 2011 MacBook Pros with Ubuntu and found that a few terminal commands would get things working. I used Andy Bleaden’s steps from this AskUbuntu answer. I’ve pasted the steps below to ensure I always have ready access to it.
From Andy Bleaden:
I always recommend removing and reinstalling the broadcom drivers using your terminal
In a terminal type the following command
sudo apt-get purge bcmwl-kernel-source
sudo apt-get install bcmwl-kernel-source
This will then rebuild your driver.
You can either restart your pc or if this is a pain type the following commands in the terminal which will ‘switch on’ your wireless
sudo modprobe -r b43 ssb wl
sudo modprobe wl