docker学习的问题3--Error response from daemon: This node is not a swarm manager.

问题：

[[email protected] ~]# docker network create -d overlay --subnet 172.16.1.0/24 --gateway 172.16.1.254 ol1
Error response from daemon: This node is not a swarm manager. Use "docker swarm init" or "docker swarm join" to connect this node to swarm and try again.

解决办法：

[[email protected] ~]# vim /usr/lib/systemd/system/docker.service
ExecStart=/usr/bin/dockerd --containerd=/run/containerd/containerd.sock    #修改这一行内容
[[email protected] ~]# systemctl daemon-reload
[[email protected] ~]# systemctl restart docker

验证：

[[email protected] ~]# docker network create -d overlay --subnet 172.16.0.0/24 --gateway 172.16.0.254 ol1
52087a37d9a0c9d977618212a929bf8aea5fbc7c2cbb0b6f02b90e7d2621af3b