CasaOS on macOS with External Drives

Previously, I wrote about how to install CasaOS on macOS, both as a written guide and in a video. I received several similar questions, such as:

• Any way to mount external volumes? Without volumes, it is useless. Please someone help.
• How can I share my actual hard disks on CasaOS?
• Thanks for the tutorial, it works great. How do I configure an external USB HDD? Thank you.
• It is working perfectly, but we have one “big” problem. I have three other external drives and I couldn’t mount them all into CasaOS.

Basically, many of you wanted to know how to mount external drives to CasaOS on macOS. That makes sense, because Apple charges a premium for large internal storage, and it’s usually much cheaper to expand your homelab storage using external drives.

Accessing external drives from CasaOS on macOS is a bit tricky. That’s because the CasaOS instance running on macOS is virtualized, not fully native. However, that doesn’t mean mounting external drives is impossible.

Enough chit-chat—let’s get started!

Not in the mood for reading? Watch the video instead.

Requirements

• CasaOS on macOS already installed

Configuration Steps

• Open your favorite Terminal app.
• Check the status of your colima service using colima status. If it’s running, stop it with the following command:

colima stop

• Attach your external drive (SSD or HDD). It’s recommended to use a drive formatted as APFS or HFS.
• Create an empty directory dedicated to CasaOS, for example casaos-data, on your external drive.

# Replace ExternalSSD with your actual external drive name
mkdir -p /Volumes/ExternalSSD/casaos-data

• Edit the colima.yaml configuration file using your favorite text editor.

open ~/.colima/default/colima.yaml

• Locate the mounts: [] section and update it. Add your $HOME directory as the first entry, followed by your external drive paths. Below is an example with one external drive.

# Configure volume mounts for the virtual machine.
# Colima mounts the user's home directory by default to provide a familiar
# user experience.
#
# EXAMPLE
# mounts:
#   - location: ~/secrets
#     writable: false
#   - location: ~/projects
#     writable: true
#
# Colima default behavior: $HOME is mounted as writable.
# Default: []
mounts:
  - location: /Users/junian
    writable: true
  - location: /Volumes/ExternalSSD/casaos-data
    writable: true

• Note: Don’t forget to replace /Users/junian with your own $HOME path and /Volumes/ExternalSSD/casaos-data with the path to your external drive.
• Save the colima.yaml file and return to your Terminal.
• Start the colima service again.

colima start

• Open http://localhost/ in your favorite browser and log in to your CasaOS account.
• Open the File Explorer inside CasaOS. Click ROOT in the sidebar, and you should see your external drive listed there.
• You can store any files (movies, music, photos, documents, etc.) on the drive. Files are accessible from both CasaOS and macOS.
• Finally, have fun with it!

Video

Conclusion

That’s how you mount external drives to your CasaOS instance on macOS. It’s a bit of a hassle at first, but it’s actually quite easy once you know the steps.

As usual, if you have any questions or a better method, feel free to leave a comment below. Thanks for reading, and see you next time!