Set sparse to an external VHDX.

[hpx502766238]

I have set sparseVhd=true in .wslconfig then ,copy a clean vhdx from another distribute to E:\data.vhdx then

wsl --shutdown
wsl --mount --vhd "E:\data.vhdx"
lsblk
sudo mkfs.ext4 /dev/sdc
wsl --shutdown
wsl --mount --vhd "E:\data.vhdx"
wsl --cd /mnt/wsl/Edatavhdx

Then I can write files to this external vhdx in wsl,but it cannot shrunk size automally after file was deleted. It seems that only system vhdx was supported. wish wsl to support setting sparseVhd to external vhdx.

[github-actions[bot]]

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[hpx502766238]

Logs are required for review from WSL team

If this a feature request, please reply with '/feature'. If this is a question, reply with '/question'. Otherwise please attach logs by following the instructions below, your issue will not be reviewed unless they are added. These logs will help us understand what is going on in your machine.

How to collect WSL logs

/feature

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Diagnostic information

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[OneBlue]

@hpx502766238: You mark set a vhd as sparse by calling: fsutil sparse setFlag C:\path\to\vhd before the disk is mounted inside WSL.