It’s a little too vague of a question. It’s like asking, “What is the best car for me?”
Well. How much do you want to spend? Do you have a family? Do you have a budget for fuel, service and maintenance, and insurance? So many factors to consider.
It might not be necessary for you to backup the entire server. You could just backup parts of the system, such as just the xx network related parts. The following posts show how you can backup xx network data to a tarball and rather than migrate the data to a new computer, store the tarball somewhere safe in the event of a disaster.