Ubuntu Xenial Xerus released - includes beefed up support for ZFS and containers

Canonical's latest package includes long-term support for enterprise customers

The latest version of Ubuntu, featuring a version of the OpenStack cloud framework called Mitaka, the container hypervisor technology LXD and full support for the ZFS file system is released on 21 April.

Dubbed Xenial Xerus, in keeping with Canonical's tradition of naming its releases after animals (a xerus is an African ground squirrel), Ubuntu 16.04 LTS is the latest long-term support (LTS) release of the popular Linux distribution. The company offers five years of updates and technical support for enterprise customers with a support agreement. Other releases occur at six monthly intervals.

The previous LTS release was version 14.04, which was launched two years ago with OpenStack Icehouse. Canonical tied its release cycle for Ubuntu to that of OpenStack back in 2013, so that the latest version of the operating system always comes with the newest version of the cloud platform.

"We are the only distribution to stay in step with OpenStack, and the reason is because OpenStack is maturing fast, and every release brings with it meaningful functionality," said Canonical's Anand Krishnan, executive vice president and general manager of cloud.

Two features in OpenStack Mitaka have been significantly enhanced in the latest release: live migration and Cells v2, Krishnan said. Live migration enables the system to move a virtual machine from one physical host to another without disrupting the workload inside it, while Cells makes it easier to scale out a deployment.

There are additional refinements designed to support containers in Xenial, too. The first of these is the ZFS file system, which was originally developed by Sun Microsystems for its Solaris Unix platform. ZFS offers a high level of data integrity, compression and snapshots.

"ZFS has a whole host of features that people have often said would be great to have on Linux, and OpenZFS has been available as a project, but no-one has actually pulled it into a Linux distribution until now, and it will make the lives of sysadmins, especially anyone handling storage of any complexity, much better," Krishnan said.

Ubuntu 16.04 LTS also features a new version (2.0) of Canonical's LXD (Linux Container Daemon) container technology, with tweaks for greater stability and a Nova plug-in for better integration into OpenStack. LXD enables the operating system to treat containers in pretty much the same way as virtual machines, providing better security and isolation between containers.

"LXD is bare-metal performance, but with a VM-like construct around it. It looks like a VM, and it acts like a VM, but it is really a container. If you run a job in LXD, you immediately lose that 15 to 30 percent overhead that a VM would impose," Krishnan explained.

In this it differs from Docker, which is basically a way of packaging and distributing applications inside containers. However, Docker can be run inside an LXD container.

Meanwhile, Ubuntu 16.04 LTS introduces its own application format, called the snap package, based around Canonical's "snappy" transactional update mechanism. This enables developers to build isolated applications that can be deployed and updated much more easily, according to Canonical.

Ubuntu 16.04 LTS has also been ported to run on IBM's z Systems, enabling scale-out Linux workloads to be brought to mainframe systems such as the LinuxOne family for customers such as banks and insurance companies, Canonical said.