18.04 hangs on boot after system software update

Question

I have two users on a fresh install of Ubuntu 18.04.

Normally I work with user1. Today I switched to user2 and started software update. (As far as I remember a few things were installed and some unnecessary ones removed).

When I rebooted it stopped for a long time at the first dot of the splash screen. So I pressed Ctrl+Alt+Del. Then the system shut down.

Now system boots until the splash screen and then switches to text mode. Last message:

ubuntu 18.04 boot  "Started GNOME Display Manager. Dispatcher Service ....rfkill Watch.   
Started Restore /etc/resolv.conf if the system crashed before the ppp link was shut down."

With Ctrl+Alt+F1/F2 I can log in. The first time a message appeared that Canonical live patch applied 0 or so.

The machine is normally running 7/24 and is very important to me! How should I proceed?

EDIT:

now comes: ubuntu 18.04 boot "started GNOME Display Manager. Dispatcher Service ....d before the ppp link was shut down"

Exactly which kernel? (It's important - one has a critical bug in process as of 03 July 2018) — user535733, Jul 04 '18 at 21:51
I can login user ctrl + alt + f1 f2. uname -r says 4.15.0-24-generic. I'm new to linux. Should I proceed as described here? https://askubuntu.com/questions/1051555/after-security-update-to-4-15-0-24-generic-26-ubuntu-screen-shows-log-content — ssssstut, Jul 04 '18 at 22:09
I agree you have the "bad" kernel. Try to boot into the previous one. — Organic Marble, Jul 04 '18 at 22:13
neither left shift nor right shift works to get to grub menu. Can anyone recommend which steps I need to do? — ssssstut, Jul 04 '18 at 22:22
It's a standard ubuntu 18.04 installation. How can I get into grub menu to select a previous kernel? shift didn't do anything — ssssstut, Jul 04 '18 at 22:30
(For me it was hitting ESC multiple times) however when I boot with 0-23-generic I get the same error message, What should I do now? — ssssstut, Jul 04 '18 at 22:45
Since it's a new install, one option is to reinstall with a -23 or older kernel. — user535733, Jul 04 '18 at 22:49
It booted now. What did I do (see link above) 1. boot 23. 2.install lightdm. 3. reboot --> black screen. 4. reboot to 23. 5. sudo dpkg-reconfigure lightdm --> selected old one. 6. rebooted. worked. Don't know if it works again if i reboot again. — ssssstut, Jul 04 '18 at 23:26
Possible duplicate of After "security update" to 4.15.0-24-generic #26-Ubuntu screen shows log content not login — WinEunuuchs2Unix, Jul 05 '18 at 01:50

18.04 hangs on boot after system software update

0 Answers0

Linked