> Before Erlang, Tandem systems built hardware/software with many of the same ideas in them.

Indeed, Jim-gray's (from tandem) paper 'why computers stop and what we can do about it' is an quite good. It contains a detailed report of machine failure including s/w and h/w and details techniques for reducing the mtbf by these.

Erlang's language and runtime seems to have picked seminal ideas from here...