Is a clean install better than upgrading?

Is it better to install Ubuntu completely new or is the upgrade process just as good? In other words, will my computer run just as problem-free and efficiently when I upgrade as opposed to a fresh install?

Typically, upgrades are just fine in Ubuntu. It's not like Windows where you have a huge registry to carry over from your last system. As long as you haven't had to follow many tutorials or done any workarounds to fix problems in a unique way (i.e. using a special application to enable your wireless card or made some major changes to your kernel for whatever reason) you'll be fine.

In fact, I'd say about 90% of people who are asking this question will be fine with the upgrade.

If you want to stay absolutely safe, you can always wait for the vetted point release upgrade, or even maybe wait for the next LTS release in a few years. It's your choice. You'll still be supported for the next three years with updates if you're on 10.04 right now.

That depends what you use Ubuntu for.

• If your installation is only a toy or an appliance (e.g. just for web browsing) and you haven't customized it, reinstall. Make sure you save any personal data (typically you'll want to back up your home directory and restore selected parts).
• If the only customizations you've done on your installation are to install additional drivers or make other tweaks because your hardware was poorly supported under the old version, it may be better to do a clean reinstall.
• If you've customized your installation in any other way (configured system settings, installed more than a couple of additional programs, etc.), upgrade. If you've used Ubuntu actively, this case probably applies (if nothing else, you're likely to have installed a bunch of packages).

At the system level, Ubuntu is very good at smooth upgrades. Upgrades are tested before each release. This is a supported mode of operation, and it's more likely to leave you with the system you want than reinstalling and trying to remember all your customizations.

At the user level, Ubuntu's default interface is Gnome, which is not so good at importing settings from one version to another. Thus the choice is between

• starting from a fresh home directory and restoring all documents and selected settings from a backup; and
• keeping your home directory across the upgrade, and looking into the problem if something goes wrong.

In either case, you might as well do a system upgrade.

Generally a fresh install is preferred for the reason I have seen a lot of issues with the upgrading process. Upgrading process generally ends up going in some crappy graphic driver problem or a GPU one. I even got weird problems, like non availability of shared folders and data loss.

Well its all up to you, as problem also persists when you are going for a clean install. But clean install problems are generally easily understood and recoverable.
Well enjoy installing Ubuntu :)

There are no guarantees in life

You can have crashes in a fresh install or in an upgrade. Most people will not experience a crash. If you are in that unlucky minority it is best to:

• have a backup you can restore or,
• test the install/upgrade on a separate partition.

Clean install advantages and disadvantages

For a clean install all that old garbage you've installed over two years between LTS versions is gone. This however can be a disadvantage as you often forget the good stuff you've added in /usr and /etc subdirectories.

Upgrade advantages and disadvantages

In the process of upgrading you are told for each configuration file what each new package version will be changing. You can select to keep the old or take the new version. For example during Ubuntu 16.04 LTS to 18.04 LTS upgrade these changed on my system:

• Scanner configuration - /etc/sane.d/dll.conf
• /etc/NetworkManager/conf.d/default-wifi-powersave-on.conf
• Sound override to keep HDMI TV active - /etc/pulse/default.pa
• Grub override to hide menu at boot unless Escape pressed - /etc/grub.d/30_os-prober
• Cron(you would loose all on fresh install!) - /etc/cron.d/anacron
• Total network traffic monitoring utility - /etc/vnstat.conf

Running the upgrade on May 6, 2018 I was told that 203 packages will be removed. Over time support for more packages will be added so fewer will be dropped during upgrade. It is best to ensure all your critical needs packages are there or you have alternatives from other developers to use.

Backup first or run upgrade on cloned partition

Backing up and restoring is a pain. It's time consuming and often times your restore doesn't proceed as planned. An alternative is to clone your 16.04 LTS (or whichever version) to a new test partition and upgrade to 18.04 LTS (or whichever version) there.

I use a script to clone Ubuntu to a test partition for upgrading: Bash script to clone Ubuntu to new partition for testing 18.04 LTS upgrade

The script will:

• Use rsync to ensure mirror image from real partition to test partition
• Update test partition /boot/grub/grub.cfg with proper UUID's for booting
• Update test partition /etc/fstab with proper UUID's for booting
• Run sudo update-grub to add test partition to boot menu
• Allow you now reboot and run upgrade on test partition

After upgrade on test partition you can take your time exploring all the new features and checking for bugs. You still have your original Ubuntu installation for day to day work. If you find bugs in the new version, you can rerun the cloning and upgrade a week or two later after they have been fixed. You would also re-clone and re-upgrade if packages critical to your work were not supported but now support has been added.