Failed to start cri-docker.socket.service: Unit cri-docker.socket.service not found.

[hualongfeng]

I installed cri-docker. but error on service cri-docker.socket start. System: Ubuntu22.04

root@minikube:~/cri-dockerd# systemctl enable cri-docker.service
root@minikube:~/cri-dockerd# systemctl enable --now cri-docker.socket
root@minikube:~/cri-dockerd# service cri-docker.socket start
Failed to start cri-docker.socket.service: Unit cri-docker.socket.service not found.
root@minikube:~/cri-dockerd# service cri-docker start
root@minikube:~/cri-dockerd# service cri-docker status
● cri-docker.service - CRI Interface for Docker Application Container Engine
     Loaded: loaded (/etc/systemd/system/cri-docker.service; enabled; vendor preset: enabled)
     Active: active (running) since Mon 2022-11-28 11:56:08 UTC; 4h 2min ago
TriggeredBy: ● cri-docker.socket
       Docs: https://docs.mirantis.com
   Main PID: 28534 (cri-dockerd)
      Tasks: 35
     Memory: 17.1M
        CPU: 9.418s
     CGroup: /system.slice/cri-docker.service
             └─28534 /usr/local/bin/cri-dockerd --container-runtime-endpoint fd://

Nov 28 11:56:08 ceph-server5 cri-dockerd[28534]: time="2022-11-28T11:56:08Z" level=info msg="The binary>
Nov 28 11:56:08 ceph-server5 cri-dockerd[28534]: time="2022-11-28T11:56:08Z" level=info msg="The binary>
Nov 28 11:56:08 ceph-server5 cri-dockerd[28534]: time="2022-11-28T11:56:08Z" level=info msg="Loaded net>
Nov 28 11:56:08 ceph-server5 cri-dockerd[28534]: time="2022-11-28T11:56:08Z" level=info msg="Docker cri>
Nov 28 11:56:08 ceph-server5 cri-dockerd[28534]: time="2022-11-28T11:56:08Z" level=info msg="Docker Inf>
Nov 28 11:56:08 ceph-server5 cri-dockerd[28534]: time="2022-11-28T11:56:08Z" level=info msg="Setting cg>
Nov 28 11:56:08 ceph-server5 cri-dockerd[28534]: time="2022-11-28T11:56:08Z" level=info msg="Docker cri>
Nov 28 11:56:08 ceph-server5 cri-dockerd[28534]: time="2022-11-28T11:56:08Z" level=info msg="Starting t>
Nov 28 11:56:08 ceph-server5 cri-dockerd[28534]: time="2022-11-28T11:56:08Z" level=info msg="Start cri->
Nov 28 11:56:08 ceph-server5 systemd[1]: Started CRI Interface for Docker Application Container Engine.
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[neersighted]

Your cri-dockerd is running just fine: service cri-docker.socket start is meaningless as the service command is hardcoded to use a .service unit suffix.

To break down what happened/why this is not a problem:

• systemctl enable cri-docker.service - cri-dockerd can now start
• systemctl enable --now cri-docker.socket - cri-dockerd's socket is now being monitored by systemd (both now, and on subsequent reboots)
• TriggeredBy: ● cri-docker.socket - your cri-dockerd service was started by systemd automatically as someone tried to connect to the socket

In short, the service command here is a legacy wrapper for admins used to working with init scripts, and cannot reason about systemd socket activation units.