创建容器时添加参数 --restart=always 后，当 docker 重启时，容器自动启动。
使用方法：
docker container update --restart=always 容器名字
操作实例如下：
[root@localhost mnt]
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
46cdfc60b7a6 nginx "nginx -g 'daemon ..." About a minute ago Up 42 seconds 80/tcp n3
79d55a734c26 nginx "nginx -g 'daemon ..." About a minute ago Up 42 seconds 80/tcp n2
f7b2206c019d nginx "nginx -g 'daemon ..." About a minute ago Up 46 seconds 80/tcp n1
[root@localhost mnt]
n1
[root@localhost mnt]
[root@localhost mnt]
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
46cdfc60b7a6 nginx "nginx -g 'daemon ..." 2 minutes ago Exited (0) 5 seconds ago n3
79d55a734c26 nginx "nginx -g 'daemon ..." 2 minutes ago Exited (0) 5 seconds ago n2
f7b2206c019d nginx "nginx -g 'daemon ..." 2 minutes ago Up 2 seconds 80/tcp n1
