Clement 'Clem' Lefebvre, the head of the Linux Mint team has announced the official upgrade path to move machines over from Linux Mint 17.3 to version 18. If you thought the days of not needing to drop into the Terminal were over, then you were wrong, as the upgrade method is solely command-line based.
In the announcement, Lefebvre is insistent that users should only upgrade their machines if they have a specific reason to do so. He also repeats the usual Mint line of: “if it ain't broke, don't fix it.” To lessen the number of broken upgrades, the 'mintupgrade' command line tool comes equipped with a 'check' command which temporarily points your system to different repositories to calculate the upgrade process and whether any problems would occur if it was actually done; once it has checked, your system's settings are reverted back to normal.
On whether users should use mintupgrade, Lefebvre writes:
“Linux Mint 13 is supported until 2017 and Linux Mint 17, 17.1, 17.2 and 17.3 are supported until 2019. You might want to upgrade to Linux Mint 18 because some bug is fixed or because you want to get some of the new features, in any case, you should know why you're upgrading. As excited as we are about Linux Mint 18, upgrading blindly for the sake of running the latest version does not make much sense, especially if your already happy and everything is working properly.”
Judging by his comments, it appears as though the Linux Mint boss wants people to either stick with what they have or backup and migrate to Mint 18 via a clean install. Admittedly, his method is more sensible given the moderate risk of breakage or weirdness (such as strange behaviour, missing icons etc.) that can occur when upgrading a system.
The Mint team does allow users to upgrade between point releases via the update manager because of the ease and low chance of systems breaking from the upgrade; however, the team didn't include this option for moving to Mint 18 because it's a major upgrade with a whole new base. One Mint user asked Lefebvre why the decision to use the command line to update systems was taken; here is the brief question and response:
Question: The upgrade worked! One question though – why the command-line upgrade, rather than through the Upgrade Manager?
Lefebvre: Because of the nature of the upgrade, the output coming from APT is really important. Also, this is the first time we support a base jump. Using the command line meant we didn't need to focus on a lot of other things which could go wrong if we had used a UI. This upgrade requires good APT knowledge, so although it would be more comfortable to use a UI, it might deceive novice users into thinking it's ok to just click Next without reading what's written. I say this with experience and without judging, but it is our job to warn people appropriately. From a technical side also, this is not comparable to the upgrades between point releases, which is trivial and much more predictable. Here, a lot of things can go wrong depending on the user's system and the packages installed. It's important the user reads the output, understands it and responds to it appropriately.
For the users out there who want to brave the rough seas of an in-place upgrade, testing Linux Mint 18 in live mode is essential so that pre-cursory checks can be made to see if all the computer hardware is compatible. Unfortunately, the upgrade process is only available to MATE and Cinnamon editions of Linux Mint 17.3.
Source: Linux Mint Blog