Simple way to change default kernel? - solved

[benchrest]

I have a nuance bug with 4.15.0-112 and 4.15.0-115 kernels that resolves if I boot from 4.15.0-111. I can manually change the kernel at boot but I need to do it each time I boot. Is there a simple way to set the kernel I want to boot from as default until a new kernel comes out and then switch back to test the new one if not fixed go back to .111? Because the bug is a nit (an unwanted blink on resume from inactive that adds all of 3 seconds to my resume). I'm just irritated by this regression. I don't expect it will have a high priority to be fixed so this could go on a long time. Maybe I just need to take my pills.
I also noticed I have kernels starting 5.4, 5.3 5.0 and 4.18 besides the kernel I am running 4.15 Should I try one of them, I am on LM Cinnamon 19.0 with dual screens and Nvidia? I am not sure why these kernels have downloaded if I am only to run 4.15
I am not interested in upgrading to 19.1 or 19.2 as they both caused problems for me. 19.0 has done just what I want to this point. I do realize at some point I need to bite the bullet.
Rich

[DAMIEN1307]

Just manually boot into the kernel that you know works ok.

As soon as your booted up, go into the kernels section of the update manager and remove/uninstall the offending kernels from there.

You can then further clean up the left overs from the kernel removal by copy and paste the codes provided below into your terminal.

Code: Select all

sudo apt autoremove --purge

Code: Select all

dpkg -l | grep '^rc' | awk '{print $2}' | sudo xargs dpkg --purge

Now just reboot and all should be as before.

be sure that as soon as the update manager shows you to update again to the offending kernel/kernels...right click on those entries and click to ignore.

once a new kernel becomes availabile that no longer has issues, you can safely take the offenders out of the ignore list.

[benchrest]

In displaying the kernels to delete I noticed /remembered it also showed 4.15.0-117. But my system did not boot from it automatically but from 4.15.0-115. Also I could not find 4.15.0-117 installed in the kernel history. Makes me wonder if there was an error installing it. So I deleted the three kernels, -112, -115 and -117. No errors. Then I ran your two commands. The first one listed what it was going to do and -111 was not included. But when it executed it attempted to delete -111 !!. I answer yes to skip the delete. After the commands were completed ir rebooted and it would not. Got text messages on black screen. So I attempted to use grub for advanced settings and had two choices, -111 and -20 (the very oldest). Tried -111 and failed with the text messages again. Then tried -20 and it booted, but low resolution and one monitor. I went into update monitor and it gave me the option to install -117. I took it. I then went to kernel listing and it did not show -111 installed so I installed it. Now have -20, -111 and -117 installed. rebooted and -117 loaded but still one monitor low res. Went to drivers and showed an older nvidia driver installed and installed the recommended driver 440.95.01. Restarted and all is well.
Perhaps my bug was created by -117 not being installed correctly? Anyhow I am running on -117 and will see if after 30 minutes when the monitors turn off if I get the extra blink on awake. If so I might just delete -117 and skip the two commands.
Thanks for your suggestion of just deleting the offending kenels.
Rich

[benchrest]

My blinking problem occurs with -117. But on to my original question. As I was guided, with advanced options in GRUB I booted from ther old kernel -111 and then from update manager deleted -117. Then rebooted and -111 kernel was loaded. Then from update manager marked -117 not to be installed. Not to difficult. Rich

[DAMIEN1307]

I am glad that at least that part of the solution worked for you...DAMIEN