The option -D will put your machine into the development-release 16.04. Just look at the last few lines of your attached log-file:
2015-12-25 19:52:00,602 DEBUG entry '# deb http://ppa.launchpad.net/gezakovacs/ppa/ubuntu xenial main # disabled on upgrade to xenial' was disabled (unknown mirror) 2015-12-25 19:52:00,602 DEBUG examining: 'deb http://ppa.launchpad.net/nilarimogard/webupd8/ubuntu trusty main' 2015-12-25 19:52:00,607 DEBUG entry '# deb http://ppa.launchpad.net/nilarimogard/webupd8/ubuntu xenial main # disabled on upgrade to xenial' was disabled (unknown mirror) 2015-12-25 19:52:00,607 DEBUG examining: 'deb http://ppa.launchpad.net/webupd8team/unstable/ubuntu trusty main' 2015-12-25 19:52:00,612 DEBUG entry '# deb http://ppa.launchpad.net/webupd8team/unstable/ubuntu xenial main # disabled on upgrade to xenial' was disabled (unknown mirror) 2015-12-25 19:52:00,612 DEBUG examining: 'deb http://ppa.launchpad.net/ubuntu-x-swat/x-updates/ubuntu trusty main' 2015-12-25 19:52:00,617 DEBUG entry '# deb http://ppa.launchpad.net/ubuntu-x-swat/x-updates/ubuntu xenial main # disabled on upgrade to xenial' was disabled (unknown mirror) 2015-12-25 19:52:00,617 DEBUG examining: 'deb http://ppa.launchpad.net/xorg-edgers/ppa/ubuntu trusty main' 2015-12-25 19:52:00,622 DEBUG entry '# deb http://ppa.launchpad.net/xorg-edgers/ppa/ubuntu xenial main # disabled on upgrade to xenial' was disabled (unknown mirror) 2015-12-25 19:52:00,623 DEBUG examining: 'deb-src http://ppa.launchpad.net/gezakovacs/ppa/ubuntu trusty main' 2015-12-25 19:52:00,627 DEBUG entry '# deb-src http://ppa.launchpad.net/gezakovacs/ppa/ubuntu xenial main # disabled on upgrade to xenial' was disabled (unknown mirror) 2015-12-25 19:52:00,628 DEBUG examining: 'deb-src http://ppa.launchpad.net/nilarimogard/webupd8/ubuntu trusty main' 2015-12-25 19:52:00,632 DEBUG entry '# deb-src http://ppa.launchpad.net/nilarimogard/webupd8/ubuntu xenial main # disabled on upgrade to xenial' was disabled (unknown mirror) 2015-12-25 19:52:00,633 DEBUG examining: 'deb-src http://ppa.launchpad.net/webupd8team/unstable/ubuntu trusty main' 2015-12-25 19:52:00,637 DEBUG entry '# deb-src http://ppa.launchpad.net/webupd8team/unstable/ubuntu xenial main # disabled on upgrade to xenial' was disabled (unknown mirror) 2015-12-25 19:52:00,637 DEBUG examining: 'deb-src http://ppa.launchpad.net/ubuntu-x-swat/x-updates/ubuntu trusty main' 2015-12-25 19:52:00,642 DEBUG entry '# deb-src http://ppa.launchpad.net/ubuntu-x-swat/x-updates/ubuntu xenial main # disabled on upgrade to xenial' was disabled (unknown mirror) 2015-12-25 19:52:00,642 DEBUG examining: 'deb-src http://ppa.launchpad.net/xorg-edgers/ppa/ubuntu trusty main' 2015-12-25 19:52:00,647 DEBUG entry '# deb-src http://ppa.launchpad.net/xorg-edgers/ppa/ubuntu xenial main # disabled on upgrade to xenial' was disabled (unknown mirror) 2015-12-25 19:52:00,647 DEBUG examining: 'deb http://dl.google.com/linux/chrome/deb/ stable main' 2015-12-25 19:52:00,652 DEBUG entry '# deb http://dl.google.com/linux/chrome/deb/ stable main # disabled on upgrade to xenial' was disabled (unknown mirror) 2015-12-25 19:52:00,652 DEBUG examining: 'deb http://ppa.launchpad.net/webupd8team/y-ppa-manager/ubuntu trusty main' 2015-12-25 19:52:00,657 DEBUG entry '# deb http://ppa.launchpad.net/webupd8team/y-ppa-manager/ubuntu xenial main # disabled on upgrade to xenial' was disabled (unknown mirror) 2015-12-25 19:52:00,657 DEBUG examining: 'deb http://ppa.launchpad.net/fossfreedom/rhythmbox-plugins/ubuntu trusty main' 2015-12-25 19:52:00,662 DEBUG entry '# deb http://ppa.launchpad.net/fossfreedom/rhythmbox-plugins/ubuntu xenial main # disabled on upgrade to xenial' was disabled (unknown mirror) Not sure if this is what you really want? Too many ppa-repositories hinder an upgrade. Noone says so about the disadvantages using ppa's when it comes to Upgrade. Suffered this myself years ago. Options are you remove the packages (hopefully catch any related packages) or you make use of the ppa-purge command, which is the best recommondation (especially for xorg-edgers). ppa-purge is meant/used to replace any packages from ppa with the release-version. Since not knowing very much about your installation, it may even be recommended to make a fresh install without formatting your home- partiton. This way all your personal data wont be deleted - but you only get a basic installation. In general it's advised to follow the instructions for Upgrade from Trusty's Release-Notes: https://wiki.ubuntu.com/TrustyTahr/ReleaseNotes/14.04.3#Upgrading_from_Ubuntu_12.04_LTS_or_Ubuntu_13.10 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1529307 Title: update from 14.04 LTS to 16.04 LTS using sudo do-release-upgrade -d To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1529307/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
