Cerberus was the location of a Federation colony where Joanna McCoy went to school.
In 2259, that settlement experienced a crop failure and the entire population was in jeopardy of starvation. Fortunately, the population was saved when noted philanthropist, Carter Winston, used his personal fortune to bring in enough food and goods to carry the colony through the crisis. (TAS: "The Survivor")
Named for Cerberus, the three-headed dog that guarded the gate to Hades in Greek mythology. (citation needed • edit)
It may be located in the Cerberus system, or even be the same planet as Cerberus II.
According to the Star Trek: Star Charts ("United Federation of Planets I", "United Federation of Planets II"), the Cerberus system was located in the Beta Quadrant. This system, also known as Eta Lupi, was a single star system. Primary was a Class G star with a magnitude of +5, which was the same brightness as Sol. Cerberus was listed as a member planet of the Federation in 2378.