[ubuntu] Updating natty to latest LTS

Checking for a new ubuntu releaseYour Ubuntu release is not supported anymore.
For upgrade information, please visit:
http://www.ubuntu.com/releaseendoflife

Get:1 Upgrade tool signature [198 B]
Get:2 Upgrade tool [1471 kB]
Fetched 1471 kB in 0s (0 B/s)
authenticate 'oneiric.tar.gz' against 'oneiric.tar.gz.gpg'
extracting 'oneiric.tar.gz'
[screen is terminating]
root@bibliata:~# do-release-upgrade
Checking for a new ubuntu release
Your Ubuntu release is not supported anymore.
For upgrade information, please visit:
http://www.ubuntu.com/releaseendoflife

Get:1 Upgrade tool signature [198 B]
Get:2 Upgrade tool [1471 kB]
Fetched 1471 kB in 0s (0 B/s)
authenticate 'oneiric.tar.gz' against 'oneiric.tar.gz.gpg'
extracting 'oneiric.tar.gz'
Err http://archive.ubuntu.com oneiric/main amd64 Packages
404 Not Found [IP: 91.189.88.152 80]
Err http://archive.ubuntu.com oneiric/main i386 Packages
404 Not Found [IP: 91.189.88.152 80]
Ign http://archive.ubuntu.com oneiric/main Translation-en
Fetched 0 B in 0s (0 B/s)
Ign http://archive.ubuntu.com oneiric Release.gpg
Ign http://archive.ubuntu.com oneiric Release
Err http://archive.ubuntu.com oneiric/main amd64 Packages

Err http://archive.ubuntu.com oneiric/main i386 Packages

Err http://archive.ubuntu.com oneiric/main Translation-en

Err http://archive.ubuntu.com oneiric/main amd64 Packages

Err http://archive.ubuntu.com oneiric/main i386 Packages

Err http://archive.ubuntu.com oneiric/main Translation-en

Err http://archive.ubuntu.com oneiric/main amd64 Packages

Err http://archive.ubuntu.com oneiric/main i386 Packages

Err http://archive.ubuntu.com oneiric/main Translation-en

Err http://archive.ubuntu.com oneiric/main amd64 Packages

Err http://archive.ubuntu.com oneiric/main i386 Packages

Err http://archive.ubuntu.com oneiric/main Translation-en

Err http://archive.ubuntu.com oneiric/main amd64 Packages
404 Not Found [IP: 91.189.88.149 80]
Err http://archive.ubuntu.com oneiric/main i386 Packages
404 Not Found [IP: 91.189.88.149 80]
Ign http://archive.ubuntu.com oneiric/main Translation-en
Fetched 0 B in 0s (0 B/s)

Error during update

A problem occurred during the update. This is usually some sort of
network problem, please check your network coection and retry.

W:Failed to fetch
http://archive.ubuntu.com/ubuntu/dis...amd64/Packages
404 Not Found [IP: 91.189.88.149 80]
, W:Failed to fetch
http://archive.ubuntu.com/ubuntu/dis...-i386/Packages
404 Not Found [IP: 91.189.88.149 80]
, E:Some index files failed to download. They have been ignored, or
old ones used instead.

Restoring original system state

Aborting
Reading package lists... Done
Building dependency tree
Reading state information... Done
Building data structures... Done
=== Command detached from window (Thu Jul 28 11:47:19 2016) ===
=== Command terminated with exit status 1 (Thu Jul 28 11:47:19 2016) ===