Hi Andrew,
Looks like the systemd unit is not properly configured. I had the same
the same problem and here is a solution.
Meanwhile this is not solved in debian, you can place the systemd unit
in a way that is not going to be changed because of upgrades
```
cp -p /lib/systemd/system/docker.service /etc/systemd/system/docker.service
```
and reload systemd daemon
```
systemctl daemon-reload
```
the solution is changing the systemd unit this way [0]
Cheers,
Pedro
[0]
This patch for the systemd unit is inspired [1] by a comment of
@jordimassaguerpla available here
https://github.com/containerd/containerd/issues/386#issuecomment-304845506
```diff
[Unit]
Description=Docker Application Container Engine
Documentation=https://docs.docker.com
-After=network-online.target docker.socket firewalld.service
+After=network-online.target docker.socket containerd.service
firewalld.service
Wants=network-online.target
-Requires=docker.socket
+Requires=docker.socket containerd.service
[Service]
Type=notify
```
[1] but containerd.socket does not exist
