Ubuntu Server 16.04: what's new

Yesterday, April 21, 2016, the release of a new version of Ubuntu took place - 16.04 Xenial Xerus. It refers to the so-called LTS versions. LTS stands for Long Term Support. LTS versions are released every two years and supported by Canonical for 5 years from the date of the official release.

The ability to upgrade from the previous LTS version (Ubuntu 04/14) will appear since the release of Ubuntu 04/16/1, which will take place in about three months.
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The release of a new version of one of the most popular Linux distributions has already become the topic of lively discussions. Yesterday, an article appeared on Habré with an overview of innovations in the desktop version .

In this article, we would like to talk about what's new in the server version of Ubuntu 16.04. Its publication is timed to another important event: immediately after the official release, the image of Ubuntu 16.04 became available for installation in Vscale .

Kernel version 4.4

Ubuntu 16.04 LTS is based on the core of the latest stable version - 4.4 , which was released just a few months ago - on January 10, 2016. A brief overview of this version has already been published on Habré . A more detailed review of the changes can be found here .

Package management

As with all Debian-based Linux distributions, Ubuntu uses apt (Advanced Package Tool) to manage packages. Ubuntu 16.04 uses its new version - Apt 1.2, which is not significantly different from the previous ones, but improved from a security point of view.

In addition to the traditional deb-packages, so-called snap-packages can also be installed in Ubuntu 16.04. What is the meaning of this innovation?

Linux users quite often have to deal with the problem of dependencies, due to which new versions of many programs are very difficult to install: new versions of programs require new versions of libraries and system components that receive only security updates in LTS releases. Snap packs help solve this problem.

Unlike the deb package, the snap package includes both the application file and its dependencies. This greatly simplifies the user's life: to install the latest versions, you do not need to manually update anything and add a PPA.

Snap and deb packages can coexist without problems in the system. The main distribution format for packages in Ubuntu 16.04 is deb.

LXD 2.0

LXD (Linux Container Daemon), a tool for working with LXC containers, has been added to Ubuntu 16.04. The developers of Canonical describe it using the term lightvisor (it can be translated into Russian as a “light truck”). It was included in the official repositories back in Ubuntu 15.04. In Ubuntu 16.04, a new, improved version - 2.0 is available for installation.

LXD is integrated with OpenStack : you can manage containers using the Nova client. You can use it to run Docker images .
A detailed review of LXD features will be published on our blog very soon.

Docker 1.10

In Ubuntu 16.04, Docker has been updated to version 1.10. Existing images will need to be converted to the new format: this will be done automatically when you first start the system. Please note that the procedure of transition to the new format can take a long time and seriously load the system. Read more about this on the official Docker website .

Web servers: HTTP / 2 support

In one of the previous publications we have already discussed the features of the HTTP / 2 protocol and noted that in the near future it will be supported in all popular web servers.

The latest stable versions of Apache and Nginx have been added to the repositories of Ubuntu 16.04. Does it support HTTP / 2?

A module for HTTP / 2 support (mod_http2) has been added to Apache since version 2.4.17. So far, it is distributed in a test version , and the release date of the stable version is still unknown.
However, there is no mod_http2 in the build version of Apache2.4.18 for Ubuntu 16.04: developers have chosen not to include an unstable module in the LTS release. HTTP / 2 support is promised to be added as soon as a more or less stable version appears.

As for Nginx, version 1.9.15 is included in Ubuntu 16.04, in which HTTP / 2 completely replaced SPDY. As soon as the next stable version of Nginx is released - 1.10.0 - it will be added to the official repositories.

OpenSSH 7.2p2

A new version of OpenSSH - 7.2p2, published March 9, 2016, was added to Ubuntu. The most important innovation is as follows: it disables support for the SSH1 protocol, and also prohibits the use of DSA keys.

If you are still using an outdated key, or you need to connect to an outdated SSH server from your machine, carefully read the information published on the official Ubuntu site .

And if, for one reason or another, you are still using DSA keys, then to work with servers based on Ubuntu 16.04 you will need to generate new keys in the current format.

For developers

Vscale is a service focused primarily on developers. Their addition of a new version of Ubuntu will undoubtedly please: the newest versions of popular programming languages ​​and development tools are supported by default.

PHP 7

In Ubuntu 16.04, the "fresh" version of PHP is v7.0 available by default for installation. Compared to previous versions, it has significantly improved performance, as well as added new features - for example, the declaration of scalar types for functions and return values. However, old SAPI and extensions have been removed.

If you have previously worked with PHP 5.x applications and plan to migrate to PHP7, then you will most likely have to install updates and even make changes to the application code. The official migration guide is posted here .

Python 3.5

The new version of Ubuntu uses Python 3.5.1 by default. If necessary (for example, to support old code), Python2 can always be installed using the standard package manager:

$ sudo apt-get install python 

If you use Vim in your work, please note: it has been updated for Python3, old plugins “sharpened” under Python2 can break in new builds.

Go 1.6

The new version of the Go language was published in February - and now it is already included in the repository Ubuntu 16.04.

ZFS file system

In the 4.4 kernel, there is a native module to support the ZFS file system, which was created in the early 2000s by Sun Microsystems for Solaris OC. Then ported to other operating systems (in particular, in MacOS and FreeBSD). ZFS porting to Linux has been difficult for a long time due to licensing issues : it is distributed under a CDDL license, which is incompatible with the GNU GPL. For this reason, the very fact of adding ZFS to the mainstream core can be considered a big event.

Among the advantages of ZFS, you should first select the following:

• the ability to store large amounts of information;
• Advanced hashing algorithms for increased storage capacity
• snapshots support;
• support for storage pools;
• Endian-independence, allowing to use both big endian and little-endian devices;

ZFS is notable for its high performance (see detailed comparative reviews here and here ).

Conclusion

In this article, we briefly reviewed the main innovations implemented in the new LTS version of Ubuntu. Vscale users. can already get acquainted with Ubuntu 16.04 in practice: the procedure for creating a new server is extremely simple.

And if you want to try a new Ubuntu, but not yet a Vscale user, it's time to sign up . When registering, do not forget to specify the promotional code SCALET200, and you will receive 200 rubles to the account.

We will be happy if you share your impressions of the work with Ubuntu 16.04 in the comments. And we are looking forward to your constructive comments, suggestions and suggestions for further improving Vscale.