The serious problem with books like this one is that they are out-of-date before they get published. Where they arte useful is when you are using older hardware for something such as providing an Internet server for your personal LAN, or when you are going to try your hand at building a Beowulf Cluster from some cheap old machines. For example you could recently have bought some well-specified PII 350 machines at about£125 inclusive of delivery and tax. If you are going to do your own maintenance of such hardware, this book or one like it will be valuable. If you need up-to-date information books will not be that much use.
Book cover image courtesy of Open Library.