In the past, I’ve used Ubuntu and Minikube virtual machines for all Docker and Kubernetes development. When I looked at Docker Desktop for Windows several years ago, it just felt “lacking” compared to the other versions of Docker for Mac and Linux.
However, this week I decided to revisit the setup of my development environments by installing the latest version of Docker Desktop for Windows. One of the first things I discovered is you probably want to move the virtual hard disk used to store Docker images off the C: drive – if, like me, you run a relatively small SSD for your boot/system drive.
Note that on my primary development desktop (STORM), my C: drive is a Samsung 850 Pro 256 GB SSD – which currently has approximately 17 GB of free space. That’s not a lot, but – as long as I’m careful about what I store on system drive – it is sufficient for my needs. So, shortly after installing Docker Desktop for Windows and running a few containers, I discovered the following:
Figure 1: Disk space consumed by Docker images
Note
The screenshot above was captured after temporarily moving most of the files in my C:\NotBackedUp\GitHub folder (approximately 6 GB) to a different disk. I only mention this because some readers might notice the amount of free space at the time of the screenshot was approximately 22 GB – even with 8 GB of Docker images – which doesn’t match up with what I stated previously about currently having 17 GB of free space.
To avoid having Docker consume a large chunk on C: (again, an SSD), I moved the virtual hard disk used for storing images to a “spinning pile of rust” (as Scott Hanselman is fond of saying) – a.k.a. the “F:” drive (Seagate 3 TB HDD).
Here are the steps I used to move the ext4.vhdx file (which is stored in a docker-desktop-data folder inside the Docker folder highlighted in the screenshot above). I previously published these steps in the “STORM” page within the shared notebook used to manage the infrastructure for Technology Toolbox. I’m copying them here to make them more discoverable and easier to digest.
Move Docker images from C: drive (SSD) to F: drive (HDD)
Quit Docker Desktop
In the Windows system tray, right-click the Docker icon and click Quit Docker Desktop.
Important
Ensure Docker Desktop is not running before proceeding to the next step.
Move Docker Desktop storage (VHDX) used for images
Open a PowerShell window and run the following commands to move the virtual hard disk used by Docker Desktop to store images:
wsl --shutdown
wsl --export docker-desktop-data docker-desktop-data.tar
wsl --unregister docker-desktop-data
mkdir F:\NotBackedUp\jjameson\docker-desktop-data
wsl --import docker-desktop-data F:\NotBackedUp\jjameson\docker-desktop-data `
.\docker-desktop-data.tar --version 2
Note:
I chose to store the VHDX inside a “user” folder on the F: drive, since the file originally resided in the AppData folder for my account on the C: drive.