Fermi Linux LTS (Long Term Support) is in essence Red Hat Enterprise Linux, recompiled. What the workers in Fermilab have done is taken the source code from Red Hat Enterprise Linux (in srpm form) and recompiled them. The resulting binaries (now in rpm form) are then theirs to do with as they desire as long as they follow the License from that original source code, which they are doing. They are choosing to bundle all these binaries into a linux distribution that is as close to Red Hat Enterprise Linux as they can get it. The goal is to ensure that if a program runs and is certified on Red Hat Enterprise Linux, then it will run on the corresponding Fermi Linux LTS release.
They have built Fermi Linux LTS for Fermilab's use, and that is their ultimate goal. But they have no problems with others benefiting from their work. They have spearheaded Scientific Linux for those that want the stability of Fermi Linux LTS, but without all the Fermi modifications.
At this time, LTS is not available for users unassociated with Fermilab, but Scientific Linux provides similar functionality.
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