sysext/containerd: read drop-ins from /etc/containerd/conf.d - #4150
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sysext/containerd: read drop-ins from /etc/containerd/conf.d#4150satwiksps wants to merge 1 commit into
satwiksps wants to merge 1 commit into
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dongsupark
moved this to ✅ Testing / in Review
in Flatcar tactical, release planning, and roadmap
Changing a containerd setting today means copying the shipped /usr/share/containerd/config.toml to /etc and pointing CONTAINERD_CONFIG at the copy through a unit drop-in. The copy then misses whatever the base config gains in later releases. Import /etc/containerd/conf.d/*.toml from the shipped config instead. Snippets placed there take precedence over the defaults while the rest of the file keeps updating with the release. containerd resolves the glob to nothing when the directory is empty or absent, so a boot without drop-ins is unchanged. Fixes flatcar/Flatcar#1127 Signed-off-by: Satwik Sai Prakash Sahoo <sahoospsatwik@gmail.com>
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Right now changing a single containerd setting means copying the whole
/usr/share/containerd/config.tomlinto/etcand overridingCONTAINERD_CONFIGwith a unit drop-in. The copy then goes stale, whatever the base config picks up in later flatcar releases is silently missed.This PR adds
imports = ["/etc/containerd/conf.d/*.toml"]to both shipped configs (config.tomlandconfig-cgroupfs.toml). Snippets dropped in there take precedence over the defaults while the rest of the file keeps tracking the release. Containerd expands the glob at startup and resolves it to nothing when the directory is empty or absent, so a boot without any drop-in is unchanged. The base config is stillversion = 2, and containerd will not accept an imported file with a higher version than the main config, so drop-ins needversion = 2as well.Testing done
On a live flatcar VM (
v4593.2.4) in virtualbox via vagrant:applied the updated
config.tomlwith theimportslinewrote a drop-in at
/etc/containerd/conf.d/50-custom-log.toml:sudo systemctl restart containerdconfirmed it was merged in:
removed the drop-in and confirmed containerd still starts cleanly with an empty
/etc/containerd/conf.d/changelog/directory (user-facing change, bug fix, security fix, update)