Ubuntu 13.04 has reached end-of-life (EOL), so software updates to it are no longer available. It will continue to check for software updates, however, and fail with error messages such as:
Failed to download repository information.
and:
W: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/raring/main/source/Sources 404 Not Found W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/raring-security/main/source/Sources 404 Not Found E: Some index files failed to download. They have been ignored, or old ones used instead.
To regain a working system, upgrade to a supported release such as Ubuntu 14.04 LTS—
—by upgrading first to Ubuntu 13.10 and then to Ubuntu 14.04 LTS.
To ensure a smooth upgrade to the next release, first upgrade as far as possible by temporarily using the archived software updates for end-of-life releases:
-
Set aside the outdated software sources:
sudo mv --verbose /etc/apt/sources.list /etc/apt/sources.list_raring
-
Add the archived software sources for end-of-life releases:
sudo tee /etc/apt/sources.list <<end_of_list deb http://old-releases.ubuntu.com/ubuntu/ raring main restricted universe multiverse deb http://old-releases.ubuntu.com/ubuntu/ raring-updates main restricted universe multiverse deb http://old-releases.ubuntu.com/ubuntu/ raring-security main restricted universe multiverse end_of_list
-
Install software updates,
sudo apt-get update sudo apt-get dist-upgrade
and then reboot.
-
Restore the original software sources:
sudo mv --verbose /etc/apt/sources.list_raring /etc/apt/sources.list
-
Upgrade to the next release,
sudo do-release-upgrade
and then reboot.
-
Upgrade to the next release,
sudo do-release-upgrade
and then reboot.
The upgrade process will have disabled any third-party software sources you might have been using. Review the list in Ubuntu Software Center ▸ Edit ▸ Software Sources ▸ Other Software, and re-add any as necessary by following the instructions provided by each third party.
Examples: