3d ago

Had an issue with an update and had no networl access after reboot. How many kernals can be available in grub?

Still pretty new to Linux, I'm on Ubuntu Studio 24.04 LTS and had some issues with updates through the updater with errors and so I did sudo apt update/upgrade instead. Something went wrong and had errors, and after a reboot I had no internet access, Ethernet or WiFi, and no options to connect to anything. Running sudo lshw -c network showed unclaimed networks.

In case anyone has a similar issue, I fixed it by:

Reboot, spam shift to get into grub
Advanced options
Recovery mode for the lower number kernel
Enable networking
Fix broken packages

My question is about number 3. There were 4 kernel options, 2 normal with a recovery for each (I can't remember the specifics but one had 37 and the other 36). I selected recovery 36 as it was the older kernel. Is that amount of options (2 for each kernel) normal or can I create more? Like 37, 36, 35, 34, etc.

I was in panic mode since this PC is for work, and thought it might be nice to have more older kernel options if possible. I've also learned my lesson and am currently running Timeshift.

4 comments

If the partition where your OS stores boot images at is large enough, you can have practically infinitely many kernels in grub.
Some distros store those in a boot partition. Some store it in the root partition subdir. I don't know about ubuntu tbh.
I once had a 2gb boot partition and I needed to add a graphics stack to the boot image so I could use a touchscreen keyboard during boot to enter a LUKS password. That made a single kernel image over 1gb, so I could only have one...
- Interesting thanks. I'll look into it more.

It's been a long time since I used Ubuntu, but at the time I did I recall running into issues keeping too many old kernels. They were stored in a fixed space folder (or maybe partition?) that was like 100MB and sometimes wouldn't clear out automatically, so I remember this. May not be relevant now, but if it is, space in the storage folder is the limiting factor so you would need to change that. If it IS a partition, then you would need to deal with all that is involved with that.
edited to add that my current OS only stores three or four as well. I have never really dived into it.
- Huh, I certainly don't want to cause more issues haha. I've got timeshift setup now so hopefully if it or similar happens again and I can't get it running the kernel way I can just use that. Thanks.