Ceci est une ancienne révision du document !
My laptop is actually a MacBook Pro that I use for my work as a web developer. That being said - I always do prefer to test and program things under Linux. Specifically, I run ArchLinux with i3 on my Intel NUC, which works fine until I’m away from my desk. I’ve always intended to buy an external SSD device to put GNU/Linux on – that I can boot from when on the go. The reason for this (instead of dual-booting directly on the internal SSD) is that space is at a premium, and if I make the device removable, I can take that environment with me to other devices (although, I may need to do some fixing/tweaking). I could naturally also create a persistent USB stick, but my preference would be to have an installed system. Having now done this, I wanted to share my experiences here, for anyone who may have a similar wish. These instructions should work for any other laptop too, though you may need to tweak the information a bit.
What do I need?
• An external USB drive. The best performance will come from a USB 3.0 SSD, but for my test run, I used an old USB 3.0 1TB disk drive.
• A USB stick (check what your distribution requires size-wise).
• Your Linux distribution (in my case, Manjaro Linux).
• Your laptop.
Step 1: Create bootable USB Drive
For this step, I used Etcher (etcher.io), and simply downloaded the ISO, and selected the correct USB drive.
Step 2: Booting to USB
On a MacBook, you need to reboot and hold down the options key. For Windows-based laptops, you should be able to hit a different key to open a list of bootable devices, or change the boot device in the BIOS or UEFI settings.
In my case, the USB drive appeared as “EFI Boot”. You’ll want to use an EFI entry for newer laptops.
Step 3: Insert target USB Drive
I only plugged my external USB drive in after booting to the USB, to avoid extra options to select from. After inserting it, I checked with sudo fdisk -l what the disk was called (in my case, /dev/sdd).
Step 3b: Test environment
If you’re not sure about the distribution, or just want to make sure everything is working OK, feel free to take some time to test things at this point.
In my case, everything worked fine besides Wi-Fi. For the moment, that wasn’t a huge hardship for me (as I had a working Thunderbolt-Ethernet adapter, and my laptop was less than a meter from my switch). Instead, I hoped that some updates might fix it once it was installed. It turns out the particular device in my MacBook requires the broadcom-wl drivers. After installing and updating the kernel, I was able to reboot to a working wireless connection.
Step 4: Begin the installation
Once you’re ready, fire up the installer. Go through the typical questions until you reach the question of partitioning. I originally had hoped to pop Manjaro onto a 16GB USB thumbdrive I had, but it was unfortunately not recognized by the installer - which is why I ended up partitioning my external 1TB drive.
A few things to note here:
• Make absolutely certain you are choosing the correct drive - not the internal one.
• If you want to save your data, choose to either manually partition the drive, or to “install alongside”. If you want to erase the entire drive (for example, if it’s new), feel free to just “erase everything”.
• If you want to be more complicated and use a separate /home partition, you’ll need to configure most distributions manually. I wouldn’t recommend this on an external drive, as it just adds extra complexity to the mounting and the partition table (especially if you’re leaving an accessible partition for random data).
Step 5: Complete installation
Once the installation is complete, you just need to reboot and select the correct drive. In the case of a MacBook, you’ll want to use the EFI Boot option that appears with a hard drive icon (not the yellow removable disk option). On a Windows device, just select the device by manufacturer name in the list.
Step 6: Updates & Fixes
Once your device has booted, you’ll want to install any updates (assuming that didn’t occur during installation), fix any issues you know of, and perhaps configure your preferred software.
If you have a high DPI display, you may also want to spend some time tweaking settings for text size and such.
Downsides
From what I can tell so far, the downside is speed (a mechanical USB 3.0 drive isn’t as fast as an internal SSD). I would imagine you can improve the experience by using an external SSD, but haven’t actually tested this myself.
Other downsides can include battery life (as you’re powering another device, and in my experience, GNU/Linux power-saving isn’t always as good), and temperatures (Manjaro appears to not regulate the fans/CPU as much as MacOS did, so the laptop was running warmer than normal). These are both things that can be tweaked.
Lastly, I’ve had issues with standby under GN/Linux. I would recommend simply turning off the device.
Conclusion
The installation and booting was much easier than I had previously experienced (my last attempt at something like this failed completely due to the drive not appearing in the boot menu). And the ability to boot into GNU/Linux using a device I typically have with me anyways (external drive) is nice, especially when on a longer trip (with a C&C deadline looming!).