Lab 3.2. LXC container won't run fix

prsalinux

There's an issue on newer linux distros (24.04 in my case) where the container won't run after running "lxc-start -n unpriv-cont-user -d"
Workaround I found that worked is edit /etc/default/grub
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash systemd.unified_cgroup_hierarchy=0"
After that run "sudo update-grub" and reboot

This is another issue coming from introduction of cgroup2 and needs the materials updated accordingly.

chrispokorni

Hi @prsalinux,

The official LXC documentation still recommends its installation on earlier releases of the Ubuntu OS, predating the adoption of cgroup2.
The suggested workaround, while successful for LXC operations, could have an adverse effect on the other containerization tools and may need to be reversed.

Regards,
-Chris

prsalinux

@chrispokorni I understand that, however a large part of the lab works around docker and related tools which most certainly are keeping up with newer versions of Ubuntu and even more so this creates a conflict if LXC documentation is recommending to use earlier releases for it's own solution. LTS standard security maintenance for Ubuntu 20.04 already ended in may 2025 and can't be expected to used in a modern lab environment when new LTS versions are available for years.

This is a repeating issue through many different threads on this forum and the labs really need a refreshing update. This is a paid course and as much as I enjoy learning more from having to find workarounds, I have to find the extra time to do so next to my job.

That being said, the materials are educational, and I don't want to express lack of gratitude, but please, update them if at all possible.