When you create a new “instance” as a VM why is it creating a 10GB drive by default if you’ve selected an existing volume you already created using the volume manager INSIDE of Incus?
I had a look, but couldn’t find it. In a previous thread I am sure it was decided that the core of the Incus system needs that partition, 10GB by default, but it can also be much smaller. I am pretty sure it is adjustable within the GUI.
Incus always needing its own “root” volume seems reasonable enough, but I wonder why we can’t choose to use an existing volume as the root when making an instance. I really don’t need two “root” volumes.
It’s my understanding that the root volume is an upstream requirement of Incus.
I couldn’t find the original post myself, but @Foxtrot314 shared the following quote from the main Incus dev
The root disk must always exist and is the only one that gets snapshotted, backed up and moved around as part of the instance.
For VMs, you can make it tiny and never use it, instead relying on external disks (custom block volumes) for everything, but you can’t fully remove the root disk as it’s assumed by a lot of different code paths to be present.
I still wonder why we are forced to a 10 GB size when we import a zvol. However, if you use a Linux image, you can set the root disk size, but it is still forced to a 5 GB minimum.
EDIT
If it gives you any comfort the volumes used by Incus are sparse type, so it doesnt matter if root disk is 10GB. It will only take the real amount of data on your pool which is nothing if you dont use it.
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