An upgrade from 'zesty' to 'bionic' is not supported with this tool. Tried official links, no success

Question

I tried following https://help.ubuntu.com/community/EOLUpgrades/Feisty link, but without success. I need to upgrade my system to 17.10(EOL) from 17.04.

When running following command I am getting an error:

jenil@jenil-Inspiron-5423:~$ **sudo aptitude update && sudo aptitude upgrade**
Hit http://archive.ubuntu.com/ubuntu artful InRelease
Hit http://archive.ubuntu.com/ubuntu artful-updates InRelease
Hit http://archive.ubuntu.com/ubuntu artful-security InRelease
Ign http://archive.ubuntu.com/ubuntu zesty InRelease
Err http://archive.ubuntu.com/ubuntu zesty Release
  404  Not Found [IP: 2001:67c:1560:8001::11 80]
98% [Working]               
Current status: 0 (-1281) upgradable.
**E: The repository 'http://archive.ubuntu.com/ubuntu zesty Release' does not have a Release file.**

Answer 1

Yup, that's by design:

As you installed a development release (17.04) that had only a 9-month life span and had an End of Life (EOL) in Jan 2018, there is no way to upgrade it to 17.10 as that went EOL back in July 2018.

So as you're stuck with a release without an upgrade path (as you cannot skip versions), the only thing you can do is:

• Backup /home
• Install a new version
• Install all applications again
• Restore /home

For the future, you should:

1. Install LTS (Long-term support) versions as they have an 8-year life span (with Extended Security Maintenance) or 5 years without. The current LTS version is Ubuntu 18.04.1 LTS Bionic Beaver released on July 26, 2018 with an EOL in April 2023.

OR

2. Carefully watch the EOL of the interim / development releases and upgrade frequently.