Two years, as I follow a "famous distro" long term release schedule. My configuration is around 95+% scripted, so, while still slow to execute, it's determinis

Two years, as I follow a "famous distro" long term release schedule. My configuration is around 95+% scripted, so, while still slow to execute, it's deterministic, and I just need to copy/paste. Generally speaking, I've found that in the last years, the amount of configuration I need to update (there is always something) is getting less. My guess is that, because Linux is getting more mature, and my own setup is getting more mature as well, there are less changes in general. This is desktop, however. I also have a mini-server, server version of the same desktop distro, and I dread updating it; I find that updating configuration for server services is considerably more complex. Regarding the other questions. Why: in some cases it's a necessity. I always have modern-ish hardware, and older distros may not support, out of the box, the required kernel. Out-of-the box support also helps doing O/S updates in the long term. Apps: the set of programs I install and use are stable. I may add something, but the basic programs I use are the same. This is a big advantage (see "how" section). How: super-simple: I have a script to copy the configuration files to an external disk. I copy the files, I format the disk(s) and install the O/S, and execute the installation script (which, also, copies the files back). Important clarification: I copy/paste the script manually; this is necessary because new O/S version may cause minor breakages. Regarding the "how", an important thing is that I update the script when I add a new program or there is a configuration to update. This considerably reduces the work I need to do on O/S updates. Screw centralized configuration databases like Gconf, which some programs use "just because" (plaintext is fine; speed of configuration access is something rarely required, if ever). And screw O/Ss that don't allow this level of customization ;)