pve-storage-zfspool.adoc

Local ZFS Pool Backend

Storage pool type: zfspool

This backend allows you to access local ZFS pools (or ZFS file systems inside such pools).

Configuration

The backend supports the common storage properties content, nodes, disable, and the following ZFS specific properties:

pool

Select the ZFS pool/filesystem. All allocations are done within that pool.

blocksize

Set ZFS blocksize parameter.

sparse

Use ZFS thin-provisioning. A sparse volume is a volume whose reservation is not equal to the volume size.

Configuration Example (/etc/pve/storage.cfg)

zfspool: vmdata
        pool tank/vmdata
        content rootdir,images
        sparse

File naming conventions

The backend uses the following naming scheme for VM images:

vm-<VMID>-<NAME>      // normal VM images
base-<VMID>-<NAME>    // template VM image (read-only)
subvol-<VMID>-<NAME>  // subvolumes (ZFS filesystem for containers)

<VMID>

This specifies the owner VM.

<NAME>

This can be an arbitrary name (ascii) without white space. The backend uses disk[N] as default, where [N] is replaced by an integer to make the name unique.

Storage Features

ZFS is probably the most advanced storage type regarding snapshot and cloning. The backend uses ZFS datasets for both VM images (format raw) and container data (format subvol). ZFS properties are inherited from the parent dataset, so you can simply set defaults on the parent dataset.

Table 1. Storage features for backend zfs

Content types	Image formats	Shared	Snapshots	Clones
images rootdir	raw subvol	no	yes	yes

Examples

It is recommended to create an extra ZFS file system to store your VM images:

# zfs create tank/vmdata

To enable compression on that newly allocated file system:

# zfs set compression=on tank/vmdata

You can get a list of available ZFS filesystems with:

# pvesm zfsscan