Upgrading from Ubuntu 12.04
1520
How to install software or upgrade from an old unsupported release?
63514
How do I decide what version of Ubuntu to install?
75380
upgrading glibc to a version at least 2.17 or higher in ubuntu 12.04 LTS?
119595
Is it necessary to upgrade to 14.04 LTS or can I stand in 12.04 LTS forever with no problem?
45154
Where can I find 32-bit version of Ubuntu?
120161
Ubuntu 19.04 problems install upgrades
60606
Upgrading to Ubuntu 13.04 with live USB on dual boot system
144507
No facility exists in Update Manager to upgrade to a new version, why?
89744
Extended support for Ubuntu 12
100135
What does "upgrade to 18.04" mean?
68120
Will upgrading Windows 8 to 8.1 affect Ubuntu?
118307
Why does upgrade from 12.04 to 12.10 using a CD/DVD still require download?
35146
Will apt-get dist-upgrade upgrade my system to newer version?
16428
Upgrade to the latest PHP version in ubuntu 16.04
132533
back-up: which patitions to back-up before upgrading/reinstalling
63176
How can I update to Ubuntu 21.04?
132293
If I can, how do I install Ubuntu from Ubuntu?