How to change Docker's default Image storage location in WSL2? - windows-subsystem-for-linux

Question

How can I change the default location for storing Docker images in Windows? I currently have Docker installed on my C: drive, and the images are stored in the following location:
C:\Users\xxxxx\AppData\Local\Docker\wsl\data.
I want to change the default location to my D: drive. I am using WSL2 as the backend for Docker, and I have read that I can use the .wslconfig file to configure Docker. However, I am not sure how to set up the .wslconfig file to change the default image location. My WSL2 installation is located on my D: drive, which I installed from the Microsoft Store.
I'm using Docker version 20.10.21 and these are wsl specs
WSL version: 1.0.3.0
Kernel version: 5.15.79.1
WSLg version: 1.0.47
MSRDC version: 1.2.3575
Direct3D version: 1.606.4
DXCore version: 10.0.25131.1002-220531-1700.rs-onecore-base2-hyp
Windows version: 10.0.22000.1335
I'm using Ubuntu distro in WSL, and Docker Desktop v.4.15.0
I tried making some changes in .wslconfig but there was no option for storage or something.

Answer 1

Caveats/Preface:
I've tried this and it works, but I cannot guarantee that long-term it will continue to work. There's the potential that something will break when Docker Desktop upgrades in the future.
In general I don't recommend registry hacks, but I'm not aware of another way to do this. Other than the previous caveat, this seems fairly safe.
No, there's no .wslconfig option for changing the location of a distribution.
With that in mind, here's what I did to move docker-desktop-data to the D: drive:
Create the directory. I'll use D:\wsl\docker-desktop-data as an example.
Stop Docker Desktop by right-clicking on the status bar icon and Quit Docker Desktop.
From PowerShell:
wsl --shutdown
Confirm the location (BasePath) and registry key (PSChildName) of the docker-desktop-data via:
Get-ChildItem HKCU:\Software\Microsoft\Windows\CurrentVersion\Lxss\ |
ForEach-Object {
(Get-ItemProperty $_.PSPATH)
} | Where-Object {
$_.DistributionName -eq "docker-desktop-data"
}
Move ext4.vhdx from the BasePath directory identified above to the D:\wsl\docker-desktop-data directory.
In regedit, navigate to:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Lxss
Find the subkey matching the PSChildName from above.
Modify the BasePath to point to \\?\D:\wsl\docker-desktop-data
Restart Docker Desktop
Test that your existing images are still available by running one of them.