Docker appears to needs cgroupsv1, which is now disabled on systemd by default. As-is, the docker service then does not start with systemd, configuration detection with /usr/share/docker/contrib/check-config.sh also reports a failure. I personally saw no way to make docker use cgroupsv2. This seems to be exactly the same as Bug 691310 for libvirtd-lxc from which I took the summary description. The same solution of requiring systemd[+cgroup-hybrid] works for me.
For some reason, even with +cgroup-hybrid, check-config.sh reports failure: Generally Necessary: - cgroup hierarchy: nonexistent?? (see https://github.com/tianon/cgroupfs-mount) And dockerd doesn't start: Aug 13 02:42:45 gentoo dockerd[8340]: failed to start daemon: Devices cgroup isn't mounted Am I missing something?
Disregard the above, it was an issue with my /usr/src/linux folder. It's working with +cgroup-hybrid.
*** Bug 692040 has been marked as a duplicate of this bug. ***
It would be best if app-emulation/docker would gain a !sys-apps/systemd[-cgroup-hybrid(+)] dependency.
*** Bug 700726 has been marked as a duplicate of this bug. ***
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=9753537cfaf24e80397a0236a169ded2ccc19fdf commit 9753537cfaf24e80397a0236a169ded2ccc19fdf Author: Mikle Kolyada <zlogene@gentoo.org> AuthorDate: 2020-01-16 19:36:09 +0000 Commit: Mikle Kolyada <zlogene@gentoo.org> CommitDate: 2020-01-16 19:36:09 +0000 app-emulation/docker: force cgroupv1 on systemd Closes: https://bugs.gentoo.org/691844 Package-Manager: Portage-2.3.79, Repoman-2.3.16 Signed-off-by: Mikle Kolyada <zlogene@gentoo.org> app-emulation/docker/docker-19.03.5.ebuild | 1 + 1 file changed, 1 insertion(+)
In order to switch to cgroup1 it is enough to print a message saying to pass systemd.unified_cgroup_hierarchy=0 via kernel command line.
