Incus import command on TrueNAS Fangtooth

Incus
1

Hi,

I have two TrueNAS Fangtooth servers and have created a Windows VM on one of them. I have exported a backup of the VM and copied it to a dataset on the other server. The compressed backup file is around 12gb. The issue I am having when trying to import the backup is that the mirrored boot drive on the server has a capacity of around 13.5gb and only has around 8gb of available space. So the import gets to around 60% and gets an error saying that var/lib/incus/backup doesn’t have enough space.

I thought I had set incus to use my pool which has enough storage space. Does incus import the VM to var/lib/incus/backup before transferring it to the pool?

Is there a way to import the VM without using the boot drive?

Thanks

2

Yeah, it does.

Ideally you’d want to create two large custom volumes and then set storage.backups_volume and storage.images_volume to point to those, avoiding the writes on the boot disk.

That’d also be a strong recommendation on the TrueNAS folks to have this done by default when setting up Incus. TrueNAS already asks what pool to use, so then creating a couple of volumes on it should be easy to do during setup.

You can do it manually over the CLI with:

  • incus storage volume create default backups
  • incus storage volume create default images
  • incus config set storage.backups_volume default/backups
  • incus config set storage.images_volume default/images

That assumes the Incus storage pool is named default, I don’t remember if that’s the case on TrueNAS.

3

Merci beaucoup Stéphane.

I was able to create the volumes and set Incus to use them.

As for the naming of the Incus pools on TrueNAS, I can’t remember how I set them up initially. On one of the servers it was named default. This system was set up within Fangtooth RC1, then updated. On the other server it was named Dozer. This system was updated to the latest release of Fangtooth from Electric Eel. So I’m unsure if I had a choice to name them or if it’s just a difference between how the full release configures the pool compared to the RC1.

Upon using the newly created volumes, the import completed to 100%. I am now getting this error. Error: failed to get root disk device.

Any tips on getting this resolved?

Thanks,
Randy

4

I suspect your backup is of an instance which relied on the default profile to provide the root disk.

There’s a good chance that the TrueNAS setup doesn’t have a root device in its default profile. Adding one may fix this issue for you.

  • incus profile device add default root disk pool=NAME-OF-POOL path=/
5

Thanks again. That worked and got my instance imported and up and running.