I was running Ubuntu 14.04 LTS and the software center had been nagging to update to 16.04. Today clicked on the [Update] button in the Software Center.
Reboot proceeds until
Starting Show Plymouth Boot Screen
then multiple blank lines and
[ OK ] Started Make remote CUPS printers available locally.
I can <Super> F1 to login on tty1. I see
New release '16.04.1 LTS' available.
Run 'do-release-upgrade' to upgrade to it.
Since the upgrade does not appear to have been successful I'm reluctant to try it without advice.
do-release-upgrade. It said
No new release found.
lsb_release -a gives
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 16.04.1 LTS
startx and it appeared to start. I stopped it by
sudo stop lightdm.
If I try
sudo service lightdm start the screen alternately displays a mouse pointer and then the text boot screen, for about 5 seconds.
sudo apt-get update and got errors such as
Err:1 http://security.ubuntu.com/xenial-security InRelease
Temporary failure resolving security.ubuntu.com
Looks like I don't have network support -
ping localhost gets
ping: icmp open socket: Operation not permitted
Assuming that the upgrade has not completed, what should I do next to get to a system that boots to the GUI?
Alternatively, is it possible to back out of the update? I still have my 14.4 DVD.