Create a VM using over 80% of disk

[Alister]

I am setting up a Win10 VM and want to allocate the most space possible to it

I have a 230GiB SSD (CT250BX100SSD1) that I'm using and when I go to create the disk I get a message "not recommended to over 80%", at 190GiB 180GiB and can only create at 175GiB

The pool is showing Used 177.74 GiB and Available 45.07 GiB of 222.81 GiB

I'm not going to be using the other 45GiB for anything and there is only going to be one large file on this disk (the VM disk image) - is there any way to override the warning?

 

[sretalla]

You can probably create one at the CLI (which will just do what you tell it) and then use it during the setup, but I recommend not going over the 80% until you look at what a Copy on Write (CoW) filesystem is and then decide for yourself that it's a really bad idea.

If you decide to use all of the available space on the disk, don't expect sympathy from forum members when you lose access to your VM after you make a few writes to the disk. (although folks here will probably try to help you anyway, they may not be able to do much if your pool is 100% full)

 

[HoneyBadger]

Is this a VM being run on FreeNAS under bhyve, or a VM running on another hypervisor that's consuming the ZVOL as a datastore (eg: VMFS?)

If you're making a ZVOL there should be a checkbox for "Force Size" that will override the 80% warning. Fairly warned though that you shouldn't actually allow yourself to use 100% - assign 95% at most, but consider sparse ZVOL and letting compression get you some wins.

 

[Alister]

Is this a VM being run on FreeNAS under bhyve, or a VM running on another hypervisor that's consuming the ZVOL as a datastore (eg: VMFS?)

If you're making a ZVOL there should be a checkbox for "Force Size" that will override the 80% warning. Fairly warned though that you shouldn't actually allow yourself to use 100% - assign 95% at most, but consider sparse ZVOL and letting compression get you some wins.

Yes just using the ZVol under bhyve.

Ideally I'd pass through the disk rather than a Zvol but that wasn't an option

 

[HoneyBadger]

Ideally I'd pass through the disk rather than a Zvol but that wasn't an option

bhyve is capable of it, but it might not be exposed in the GUI - I admit I don't touch the FreeNAS VM functionality at all, that's what my hypervisor hosts are for. ;) You might be able to manually edit the config afterwards as shown here:

Virtual Disks

Shell based, minimal dependency bhyve manager. Contribute to churchers/vm-bhyve development by creating an account on GitHub.

github.com

Code:

disk0_type="virtio-blk"
disk0_name="/dev/ada10"
disk0_dev="custom"