3) Do you want a community-based or a commercial distribution?
When switching to Windows, many companies prefer to stick with what they know and deal with a commercial distribution like Xandros. With this approach, you don't need to relearn your business.
In comparison, a community-based distribution made up entirely of volunteers may seem haphazard, argumentative, and inefficient especially if you don't have techs who know how to interact with community members.
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However, don't be so quick to dismiss community-based distributions. Organizations like Debian may seem chaotic at first glance, but as you get to know them, you will find they can offer products and services as reliable as any you can find in a commercial company. Learn to appreciate them, and you can realize more of the promised savings in switching to Linux.
4) How long will the distribution last?
Many executives are nervous about open source projects because they seem less stable those of an incorporated company. What happens, they wonder, if the distribution disappears?
You can ease these fears by seeing how long the distribution has been in business and how many developers are working on it. Get your system administrator to monitor the number of software patches submitted to the distribution over a period of several weeks. On the one hand, you probably want to avoid a distribution run by three people that only began development a few months ago. On the other hand, a project like Debian, which has a couple of thousand developers and has existed for thirteen years is probably more stable than most companies.
If a distribution's duration and activity isn't enough to ease concerns, check the licenses. Most software in a distribution is released under the GNU General Public License, which gives you the right to a copy of the source code. In fact, distributions publishing under this license are required to either give you the software or offer to do so at nominal cost for copying. Assuming you have a Linux expert or two on staff, if your chosen distribution does go under, you can legally continue developing it for your own needs.
5) What training and support are available?
If you want traditional support, you can find it with most commercial distributions although you should make some comparisons to see what the current market rate happens to be. Training is less widespread, and, although Red Hat does maintain one of the leading certification programs, in many cases you may want to fall back on generic training from Sair Linux or the Linux Professional Institute.
However, even with commercial distributions, paid support and training are often last resorts. Even the smallest distributions offer free mailing lists and IRC channels for front-line help.
And if you're tempted to dismiss this free help as haphazard, think again. In more cases than not, these informal resources provide quicker and more reliable help than the traditional phone lines. Often, they give you direct access to people who designed and wrote the software you're struggling with.
Best of all, unlike with paid support, you can monitor the informal support available for a distribution before making your choice. After you do, you may decide that you don't need to choose a commercial distribution at all, or that, if you do, purchasing help is unnecessary.