Now one of the most popular flavors of Linux, Ubuntu has a reputation for being easy to use and manage. It comes with built-in KVM virtualization capabilities, and it works with Ubuntu Enterprise Cloud to allow you to create a private cloud.
Used by more than 13,000 businesses around the world, SUSE counts the London Stock Exchange, Office Depot, Sony and Walgreens among its high-profile users. In addition to the standard version, it also comes in System z, desktop, SAP, JeOS and other versions. As with Red Hat, SUSE requires commercial support; if you prefer an unsupported, free version, try openSUSE (below).
For those who don't want commercial support, the free openSUSE also comes in a server version. However, it does not have as many features and options as the commercial version.
Mandriva calls itself the "simple, high-performance, accessible Linux server." It provides Web, messaging, files, printing, virtualization and directory services. Note that the enterprise server version of Mandriva requires a fee.
When Oracle discontinued development of OpenSolaris, some of the developers who had been working on the project forked it to the Illumos project, where development and bug fixes continue. If you are looking for a free version of Solaris, this is the option for you. To download the software, visit the OpenIndiana page above.
Short for "Anti-Spam SMTP Proxy," ASSP stops spam at your mail server. Key features include easy browser-based setup, support for most mail servers, automatic whitelisting, virus scanning through ClamAV, Bayesian filters, community-based gray-listing and more. Operating System: OS Independent
This Linux distribution functions as both a network firewall and an application server. It also includes many open source network and sever monitoring tools. Operating System: Linux
This transparent proxy server works with Clam AV and other anti-virus software to scan incoming and outgoing e-mail for viruses, worms, trojans, spam and harmful attachments. Operating System: Linux
With Zentyal, you get a gateway, an infrastructure manager, a unified threat manager, an office server and/ or a unified communication server all in one package. Professional support, training and add-ons are also available on the site. Operating System: Linux
Based on the CentOS distribution of Linux, SME offers file and print sharing, mail server, network firewall, remote access, a Web application server and more. It boasts thousands of users, good security and user-friendly setup and operation. Operating System: Linux
AWStats uses the log files from your Web, streaming, FTP or mail server to create easy-to-read graphical reports. It runs from the command line or as a CGI. Operating System: Windows, Linux, OS X
The self-proclaimed "most popular logfile analyzer in the world," Analog quickly generates usage statistics for Web servers. It can be used in conjunction with Report Magic to create more attractive graphs. Note that this project has not been updated in a while, but it is still used to analyze traffic on many servers. Operating System: Windows, Linux, OS X
Like AWStats and Analyzer, Webalyzer analyzes the statistics from Web servers. By default, it creates yearly and monthly usage reports which can be viewed from any browser. Operating System: Windows, Linux, OS X
The Snare project encompasses a number of different tools and agents, all of which assist in the filtering, collection and monitoring of server log files. Commercial support and the proprietary Snare Server are also available on the same site. Operating System: Windows, Linux, OS X, others