My current setup involves one hard drive with / and one hard drive with /home. (And some NFS drives and USB backup drives, but those aren't important for this discussion)

When I replace the / drive (later this year) I'm going to use it for the first opportunity since somewhere around 2008 to start with a fresh install. I think this is also what I did last time I installed, but nearly ten years ago. Here's what I'm planning to do:

1) Have only / drive connected. (format with either ext4 or btrfs depending on how risky I feel and whether I want to take advantage of doing snapshots on yum/dnf updates)
2) Run install and create my user with the same username as now. However, I think that my current /home is so old that my username is in the 500s instead of 1000s.
3) Connect my /home drive and add it to fstab
4) chown my /home/username folder since the UID is probably wrong. Also probably need to chgrp

Anything else? Anything likely to break if I do this?

The good thing is that I'll be (hopefully) doing this before the current drive dies so if there are any config files I forget, I can always connect that drive.

That's my typical upgrade path...format root, while keeping /home as is. Makes things MUCH easier....**BUT**:

• I'd rename my user home directory to old.<username>. Why? Just try firing up a new KDE/Gnome session with the OLD directory/configurations out there...very interesting results, and ones that are hard to recover from. Easier to copy things from the old home directory to new, and let the GUI config files build themselves cleanly.
• Depending on your file system, you *MIGHT* find it better to just reload /home and put a new (faster) file system on it. Yes, it's more of a pain, but it might be worth it.

Chances are, you'll be fine, and I've done this exact thing several times in the past. This past time, though, I sprang for a new SDD for my laptop, and shoved the old one as-is into an external USB enclosure. Copied /home back after the new system was up, and I had a quick fall back plan.

Good luck.

Thanks for the advice. Glad to hear it worked out well for you. preupgrade/fedup has been working pretty awesomely for me. The combination of not wanting to deal with dd-type things since I'm hoping to get an SSD bigger than my current / drive and a few systemd things that have crept in are my main reasons for going with a fresh install. Right now I'm looking at some time next quarter, probably. To help anyone else finding the thread, I'll come back here with any lessons learned after that.