Note to self: here is how to upgrade Ubuntu 8.04 LTS (or any other release that is no longer supported) to newer Ubuntu release.
When you are upgrading unsupported release of Ubuntu if you try to do the usual
sudo apt-get update it will most likely fail because… well, it’s unsupported. The simple fix for this is to change your
/etc/apt/sources.list and replace repository URLs from something like
After that you should be able follow normal upgrade procedure (use sudo if you are not root):
apt-get update apt-get install update-manager-core do-release-upgrade
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