Multiple shared directories?

[yllekz]

Hi folks,
I'm looking to migrate away from the ever-buggier macOS Docker Desktop to a traditional Debian VM in UTM, but to do this I need the ability to mount multiple shared folders from the host into the guest VM, and currently I'm not sure if that's possible.

I'm wrapping my head around UTM shared directories. I just successfully got one working inside a Debian VM via WebDAV and mounting, but I noticed that it appears that UTM only allows for one shared directory to be mounted to a VM. I tried using symlinks but that basically doesn't work and was a dumb idea anyway. VirtualBox lets you mount a near-unlimited amount of shared folders to a VM, so I was wondering if a) it was possible in UTM, and b) if it is possible, how does one do it?

[redthing1]

This is the sole reason I switched to Parallels

[maartenSXM]

I am not sure about WebDAV but Virtfs allows additional shares. However, to do it you have to manually add a QEMU argument line per share - with each share getting a unique id and a unique mount tag.

With the guest off, go to UTM->settings->QEMU->arguments and scroll to the end of the arguments list. Then, for each additional share click 'New' to create a new argument line and adapt this to your mount path and specify a unique id (the same unique id goes in both places in the argument line) and specify a unique mount tag:
-fsdev local,id=virtfs2,path=/Volumes/extSeagate,security_model=mapped-xattr -device virtio-9p-pci,fsdev=virtfs2,mount_tag=share2

Note that in order to save your new argument line, UTM requires that you to press your <enter/return> key after adding the argument line and then only afterwards can you click the save button and have your new argument line saved.

If you want your added shares auto-mounted in a Linux guest, add lines similar to this to the guest /etc/fstab and create the guest mount paths:
share /mnt/extSamsung 9p trans=virtio,version=9p2000.L 0 0
share2 /mnt/extSeagate 9p trans=virtio,version=9p2000.L 0 0

That first fstab line is there to auto-mount the share configured from the settings->sharing dialog. The second fstab line is for an additional Virtfs share that is added manually to the QEMU arguments, as above. After adding those lines to fstab and creating the mount paths (e.g. mkdir /mnt/extSamsung /mnt/extSeagate), you will need to either reboot or issue these shell commands:
sudo mount /mnt/extSamsung
sudo mount /mnt/extSeagate

[kstlouis]

I've tried this, but the VM won't start up; I see "cannot initialize fsdev 'virtfs2': failed to open '/Volumes/temp_disk': Operation not permitted" when I go back in to edit the config

[EmmJSee]

I’m aware that this post is over a year old…but hopefully not too old.

I’m running UTM on an M2, with a Ubuntu Apple silicon guest. It runs really well, and with GPU pass through. I’ve installed this setup as the Apple ports of Darktable don’t have Metal support, so no GPU! That’s painfully slow!

I’ve successfully shared a folder using this technique. However, when I attempt to add more shares, they are not saved. I have followed these steps; adding paths to the QEMU arguments.

I would like to allow read/write sharing to folders & files within the root of this share, but I don’t want to change ownership of the files.

Should I specify the root of the share in the UI, and then add specific paths in /etc/fstab?

Any help appreciated

[maartenSXM]

Note that you have to hit return after adding the line and the click save after that. Otherwise the line is not saved.