The experienced Windows administrator who installs a single Linux machine is often bewildered by promises of administrative savings. Like any system, a single Linux machine requires administration, and while plenty of Linux administrative tools exist, they are not necessarily easier to use than Windows equivalents, particularly given the inevitable learning curve.
However, longer-term savings inherent in Linux’s proven security compared to Windows mean that Linux machines typically require less “care and feeding” than an equivalent number of Windows machines. When Linux machines are virtualized under z/VM on zSeries, the ability to perform maintenance to multiple machines simultaneously also dramatically reduces effort.
So, is Linux free or not? Linux for zSeries distributions are available for download, but do not include support. SuSE and Red Hat offer distributions with priced support; IBM offers support, but is not a Linux distributor. If an installation has experience with Linux on other platforms, a preference may exist based on the tools available with a given distribution.
If no Linux experience exists, the best advice is to visit LinuxVM at www.linuxvm. org. This site includes links to various distributions (and other resources), and should help you make an informed decision.
Whether to pay for support is a complex question, and depends largely on the skill level of your installation staff. Perversely, support is often most needed during the pilot phase, when management is least willing to pay for it. This suggests that, if possible, acquiring a distribution with a paid but time-limited support license may help ensure success.
In any case, the CIO needs to know, “How much will Linux save us?” As always, the answer is, “It depends.” In some cases, it may be possible to justify a Linux project purely based on savings on capital expenses, facilities, and software licenses. Others may require estimates of staff time saved applying service individually to dozens or hundreds of machines, or the value of improved reliability, availability, and serviceability, all of which can be difficult to quantify. No matter what, beware of generating numbers that seem “too good to be true” (even if often accurate)!
Any company has vendor applications that are critical to its operations. Unfortunately, not all of these vendors offer Linux versions, and some offer Linux versions, but not for Linux on zSeries.
Ask about vendor plans for Linux support and for Linux on zSeries support. Since “Linux is Linux,” the hardest part of porting most applications to zSeries is access to hardware; current mainframe installations may be able to work with their vendors to provide testing access in exchange for license concessions, further improving the value proposition of a migration. In more than one instance, merely asking about a zSeries version of an application has prompted a vendor to create one in a very short time.