I downloaded some Debian v.9.2.1 DVDs and I would like to know how long they are useful. In other words, how long may I retain them as install DVDs and upgrade once it has been installed and put on-line?
Also, how often would I need to replace/download new versions of the .ISOs (to ensure I could update/upgrade once installed and on-line). I know there are other ways to go about this, but I prefer to carry these install DVDs to make it easier for installing onto my systems and clients. TIA.