Use ZFS in guest ? No ZFS on host due to hardware RAID disks.

[tobiasviljoen]

AS per :

Do not use ZFS on top of a hardware RAID controller which has its own cache management. ZFS needs to communicate directly with the disks.

Proxmox is set up on HPE Server with Raid, so no ZFS on host.

That being said ... Is it possible to use ZFS inside guests without problems ?
Is the guest disk "immune" to running into problems if ZFS is used on it ?
Is there enough of a layer between guest and the hardware RAID parent disk ?

Is the type of guest disk an issue ? RAW or QCOW ?

Thanks for your comments.

 

[tobiasviljoen]

Any comments ?

Is there anyone that has experience with running ZFS on guests while the host cannot ?

 

[floh8]

zfs works on a block device. no matter if raw oder qcow2 is used

 

[UdoB]

Hi,

ZFS has some extraordinary capabilities like redundancy, checksums, self-healing, compression and so on. For some functions access to the physical disks is a hard requirement.

For this reason it is always recommended to install it directly on hardware. Not on Raid-Controllers and not on virtual drives. If you really need to run it in a virtual machine an acceptable way is to handover a disk controller in its entirety to that VM via a pass-through mechanism. (There are recommendations on which controller to buy somewhere here in the forum.)

That said: it is absolutely possible to install ZFS on any block device for teaching and/or for learning the behavior in simulated failure conditions. Just don't put any valuable data on that pool...

Just my 2 €¢

 

[floh8]

I think you are safe when you dont use raid what i expected:https://serverfault.com/questions/985252/zfs-inside-a-virtual-machine

 

[tobiasviljoen]

zfs works on a block device. no matter if raw oder qcow2 is used

Thanks,
If the virtual block device (qcow or raw) is situated on a storage device that is backed by hardware raid, is it at risk ?

 

[tobiasviljoen]

Th

I think you are safe when you dont use raid what i expected:https://serverfault.com/questions/985252/zfs-inside-a-virtual-machine

Thanks
I will read

 

[tobiasviljoen]

Hi,

ZFS has some extraordinary capabilities like redundancy, checksums, self-healing, compression and so on. For some functions access to the physical disks is a hard requirement.

For this reason it is always recommended to install it directly on hardware. Not on Raid-Controllers and not on virtual drives. If you really need to run it in a virtual machine an acceptable way is to handover a disk controller in its entirety to that VM via a pass-through mechanism. (There are recommendations on which controller to buy somewhere here in the forum.)

That said: it is absolutely possible to install ZFS on any block device for teaching and/or for learning the behavior in simulated failure conditions. Just don't put any valuable data on that pool...

Just my 2 €¢

Thank you. Noted