This article explains some considerations when choosing an operating system for your dedicated server or cloud VM. If you have any questions or need advice, feel free to contact our sales or support teams.

Narrowing Your List

The first thing to consider is what software you intend to run. For example, if you absolutely need to run Windows software, like game servers, .NET applications, desktop applications, you should choose a version of Windows. You should review the system requirements for your software carefully to find out what supported operating systems you can choose from. If you do not have any specific needs for software, we will always recommend using Linux because it offers the greatest flexibility in terms of supported software and ease of later migration.

Selecting a Linux Distribution

Steadfast Networks supports the following Linux distributions:

• CentOS
• Debian GNU/Linux

CentOS is our preferred Linux option because it has a very long life cycle and the most available software supporting it. More detail on CentOS can be found here. If you are already familiar with desktop Linux, CentOS is most similar to Fedora in how it is maintained and how files are organized. If you are familiar with Ubuntu, Debian GNU/Linux will be most similar to what you have used before.

If you have no preference, we recommend selecting the latest CentOS release available. If you specifically like the Debian-style system layout, Debian is a suitable alternative, though its support life cycle is shorter and less clearly defined. In many cases, upgrading from version to version is easier to do on Debian systems, so once a Debian release goes out of maintenance, you can use a well-documented in-place upgrade procedure to move to the new release. CentOS can be upgraded in this manner, but the procedure is not as well tested or supported. Please note that, in general, Steadfast recommends clean installations when upgrading Linux to a new major version to reduce the risk of complications. In-place upgrades are not guaranteed or officially supported by Steadfast technical support.

Why Debian instead of Ubuntu?

Steadfast prefers Debian over Ubuntu because of the additional software flexibility and stability it offers. Debian provides one of the largest software repositories of any distribution and operates on the widest variety of platforms, but also operates with one of the smallest footprints in terms of storage and memory. Debian maintains three release branches, marked stable, testing, and unstable. Stable is always the current release, which retains older but very well-tested software versions of packages with bug fixes and security patches as needed. This maintains a highly stable system which can be selectively upgraded using "backports" to access newer versions of commonly requested software if needed. The testing branch of software may also be used selectively at the risk of reducing stability of the system. Debian's support lifecycle is unfortunately somewhat ambiguous, though it has typically been 3 to 4 years. The years between releases are spent extensively testing updates and improvements nominated for the next release. Releases are not delivered until they meet specific criteria, rather than based on a routine timeline, which reduces the chances problems due to rushing. It also provides one of the most robust and reliable upgrade processes from one release to another, which mitigates a lot of the disruptions, even on production systems.

Ubuntu builds on top of Debian releases to produce frequently updated, desktop-tuned releases. We have found that Ubuntu suffers similar issues to Fedora. A new release is provided once every 6 months and only the last two are supported. After support ends, a distribution upgrade is required to continue receiving security and bug fix updates, which can be very disruptive to a production server environment. Debian supports releases for much longer and continues to hold back packages to older versions to reduce the risk of introducing instability and volatility to production environments.

Ubuntu answers this criticism with a secondary release cycle called "Long Term Support." LTS releases are made stable every fourth release of Ubuntu and receive security and bug fix updates for 5 years. This is shorter than the 10 years for Red Hat Enterprise distributions, but longer than a typical Debian release cycle. Unfortunately, our experiences with Ubuntu have indicated that package quality is often lower in Ubuntu than equivalent Debian releases and the installation process is not tuned well for server environments, which makes fast deployment and flexible installation options difficult to offer. Ubuntu has also proven more difficult to support and maintain for our customers, so we have opted to support only Debian.

Why CentOS instead of Red Hat Enterprise Linux or Fedora?

Due to the software license for Red Hat's distribution, they are required to release the source code to its components. CentOS rebuilds these packages, tests them to ensure compatibility with Red Hat's builds, and releases equivalent releases. This means that effectively CentOS is the same software release with a different name and different branding. CentOS does not include a support contract, however Steadfast Networks is intimately familiar with maintaining CentOS systems and certifies the releases on our own hardware. Since we take care of the support for you, the separate support contract isn't needed. For this reason, we don't offer Red Hat Enterprise Linux and offer CentOS as a completely compatible replacement for it. If you need RHEL for compliance of some kind, we can install it if you can provide the media and the license.

Fedora is a community-driven project intended primarily to support desktop users and help to test new software nominated for inclusion in future versions of Red Hat Enterprise Linux. Fedora releases are made once per six months, and only supported for approximately one year. After the year ends, any update to software, including for security reasons, requires you to upgrade your system to a new version of Fedora. These properties make Fedora a cutting-edge Linux distribution, but they also make the platform volatile and unstable. Upgrading the entire distribution, every six to twelve months can be very disruptive to a production server environment, so we have decided not to support Fedora on servers.

A lot of the software from Fedora considered most useful to server environments is available in a free repository called Extra Packages for Enterprise Linux (EPEL) which we can add to your server if needed.

Why not another Linux distribution?

Steadfast made determinations about which Linux distributions to support by identifying those which had the highest demand, widest support for hosting software such as control panels, best hardware support, and longest life cycle. CentOS meets these needs and satisfies most situations which require a distribution laid out like Red Hat Enterprise Linux using software packaged in RPM files. Debian meets these needs and satisfies most situations where a Debian-style system layout and software packaged in DEB format is needed.

Distributions that are very different from Debian or CentOS are rarely requested and often best suited to experienced users with specialized needs. We can attempt to install unsupported Linux distributions on servers at your request, but we can't guarantee that they'll work on our hardware or that we'll be able to fix problems with them that come up. Our modern dedicated server offerings feature remote console access (IPMI), which means you can try to install any operating system you like, if you don't mind dealing with any issues on your own. If in doubt, choosing CentOS or Debian helps ensure you server will be as reliable as possible and that we'll be able to help when something goes wrong.

Selecting a Windows Release

Steadfast supports the following Windows releases:

• Windows Server 2016
• Windows Server 2012 R2
• Windows Server 2008 R2

Steadfast currently recommends Windows Server 2012 R2.  Windows Server does not support 32-bit hardware.

Server 2008 R2 will remain supported until at least 2018 and Server 2012 will remain supported until at least 2023.

For information about Windows Server 2008 R2 editions, see this page. For information about Windows Server 2012 editions, see this page.

Why Windows Server instead of Windows 7 or 8?

Windows 7 and 8 are not considered a server-grade release and are not designed for server hardware or data center licensing. As a result, we discourage their use and do not offer licensing for them. Windows Server 2008 R2 is based on the same core as Windows 7, and Windows Server 2012 is based on the same core as Windows 8. We've found almost everything that can run on 64-bit desktop releases of Windows will run on the equivalent server release.