I encountered something very similar to this issue (maybe even this issue?) when my docker containers could not start (using snap on Ubuntu 20.04.3 LTS under VirtualBox with a Windows 10 host). Similar to others, `sudo apt install libblockdev-mdraid2` seems to have fixed it.
In case these log lines are useful context, they came from `sudo grep fail /var/log/syslog` (just trying to filter out some of the noise and I suspect that the devmapper/containerd/cni bits are not directly related): Nov 4 05:22:48 docker kernel: [ 0.305507] acpi PNP0A03:00: fail to add MMCONFIG information, can't access extended PCI configuration space under this bridge. Nov 4 05:22:48 docker systemd[1]: Starting GRUB failed boot detection... Nov 4 05:22:48 docker systemd[1]: Finished GRUB failed boot detection. Nov 4 05:22:48 docker udisksd[731]: failed to load module mdraid: libbd_mdraid.so.2: cannot open shared object file: No such file or directory Nov 4 05:22:48 docker containerd[733]: time="2021-11-04T05:22:48.627329367Z" level=warning msg="failed to load plugin io.containerd.snapshotter.v1.devmapper" error="devmapper not configured" Nov 4 05:22:48 docker containerd[733]: time="2021-11-04T05:22:48.635107136Z" level=error msg="failed to load cni during init, please check CRI plugin status before setting up network for pods" error="cni config load failed: no network config found in /etc/cni/net.d: cni plugin not initialized: failed to load cni config" Nov 4 05:22:49 docker docker.dockerd[719]: snap-update-ns failed with code 1 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1811724 Title: libbd_mdraid.so.2: cannot open shared object file To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/udisks2/+bug/1811724/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs