Arch Linux

EdeWolf

Member

Registered: 2016-01-06

Posts: 79

[solved] lxc regression?

Some change in lxc between 4.0.6 and 4.0.8 prevents unpriviledged containers with systemd as init system to start up. Reason being the container is trying to mount a non existing directory on the host:

From the containers console output:

Failed to mount cgroup at /sys/fs/cgroup/systemd: Operation not permitted
[!!!!!!] Failed to mount API filesystems.

Fair enough, as this directory does not exist. Now manually creating this directory and assigning it the proper permissions does work, but it is unclear, what to do, if multiple containers are to be started, as they all would want to mount an write into this  same dir? Therefore this is most likely not the right way of handling this.

But, what would be the proper way? Any ideas or docs I might have been missing?

Not sure, wether 4.0.7 is affected as well, but 4.0.8 is and it persists through 4.0.9. Reverting to lxc-4.0.6 resolves this issue. Quite a fundamental change for such a small increment in the versioning.

So I am doing something wrong or is this just worth a bug report?

Last edited by EdeWolf (2021-05-27 09:28:14)

EdeWolf

Member

Registered: 2016-01-06

Posts: 79

Re: [solved] lxc regression?

Just in case anybody else should ever stumble upon this:

lxc.init.cmd = /lib/systemd/systemd systemd.unified_cgroup_hierarchy=1

Did the trick. Not sure, why this requirement is new, but here we go.

Needs to be in the container config, the global lxc.conf did not work for me. Just mentioning, in case somone has only systemd based containers and wants to save some work.

forlackofabettername

Member

Registered: 2021-06-25

Posts: 1

Re: [solved] lxc regression?

Thank you for coming back to the thread and posting your solution! I've been banging my head against a wall for the last week or so trying to figure out what was going on, until I stumbled on your post.

graysky

Wiki Maintainer

From: :wq

Registered: 2008-12-01

Posts: 10,597

Website

Re: [solved] lxc regression?

Please update the lxc wiki page.

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