Using the ZFS backing store

ZFS is both a filesystem and LVM. It consists of a storage pool that manages multiple block devices and provides a virtual storage interface to the filesystem that can then easily be extended on the go. The following diagram shows the general structure of ZFS and its components:

Similar to the LVM, multiple block devices can be aggregated into a Storage pool, from which different directories can be carved.

The main features ZFS provides are data reliability due to the implementation of transparent checksums, automatic compression and deduplication of data, parallel constant time directory operations and, most importantly in the context of LXC, COW snapshots and clones.

Let's install the userspace tools on Ubuntu:

root@ubuntu:~# apt-add-repository ppa:zfs-native/daily

root@ubuntu:~# apt-get update

root@ubuntu:~# apt-get install ubuntu-zfs

The package names are different on CentOS:

[root@centos ~]# yum update

[root@centos ~]# reboot

[root@centos ~]# yum localinstall...