Is it possible to upgrade a Debian-based physical server without losing data?

Question

linux

Good afternoon, is it possible to simply upgrade the current version of the server (3.2.0-4-amd64 GNU/Linux) to the latest version without backing up all files, incl. nginx, mysql settings, etc.? For the amount of data is simply huge ~ 40-60 GB

Answer 1

Maybe. But not necessary.
For "admins are divided into three categories ..." (C) Folk wisdom
This is first. Therefore, there must be a backup. And to be more or less fresh (here, for some unknown reason, I have one wheelbarrow on which experiments are being carried out - and I think - either fuck everything and roll back the backup, or finish it off).
The major update will break everything that is possible. I don't know how old this version is, I'm not a debian, but it's a general rule that a major update breaks everything. If the program took off after the transition from version 3.x to version 4.x, for example, you are incredibly lucky.
Therefore:
- backup is required
- updating not everything in the World at once, but one subsystem at a time

Answer 2

If the server is configured correctly, the system lies on a separate partition, and everything else - on others. Accordingly, a backup of the system partition is enough to restore it in case of an unsuccessful update.