docker参数--restart=always的作用

创建容器时没有添加参数  --restart=always ，导致的后果是：当 Docker 重启时，容器未能自动启动。

现在要添加该参数怎么办呢，方法有二：

1、Docker 命令修改

docker container update --restart=always 容器名字

操作实例如下：
[root@localhost mnt]# docker ps -a
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]# docker container update --restart=always n1
n1
[root@localhost mnt]# systemctl restart docker
[root@localhost mnt]# docker ps -a
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

2、直接改配置文件（经测试后无效，修改配置文件后，启动容器后，该参数有自动变成了no，修改不生效）

首先停止容器，不然无法修改配置文件
配置文件路径为：/var/lib/docker/containers/容器ID
在该目录下找到一个文件 hostconfig.json ，找到该文件中关键字 RestartPolicy
修改前配置："RestartPolicy":{"Name":"no","MaximumRetryCount":0}
修改后配置："RestartPolicy":{"Name":"always","MaximumRetryCount":0}
最后启动容器。

修改docker容器的挂载路径

---

• 停止所有docker容器

  sudo docker stop $(docker ps -a | awk '{ print $1}' | tail -n +2)

• 停止docker服务

  sudo service docker stop

• 修改mysql路径

  cd ~
  sudo cp -r mysql/ /home/server/

• 备份容器配置文件

  cd /var/lib/docker/containers/de9c6501cdd3
  cp hostconfig.json hostconfig.json.bak
  cp config.v2.json config.v2.json.bak

• 修改hostconfig的冒号前的配置路径

  vi hostconfig.json
  
  "Binds": ["/home/server/mysql/conf/my.cnf:/etc/mysql/my.cnf", "/home/server/mysql/logs:/logs", "/home/server/mysql/data:/mysql_data"],

• 修改config的Source的配置路径
  

  vi config.v2.json
  
         "MountPoints": {
  
                "/etc/mysql/my.cnf": {
  
                       "Source": "/home/server/mysql/conf/my.cnf",
  
                       "Destination": "/etc/mysql/my.cnf",
  
                       "RW": true,
  
                       "Name": "",
  
                       "Driver": "",
  
                       "Relabel": "",
  
                       "Propagation": "rprivate",
  
                       "Named": false,
  
                       "ID": ""
  
                },
  
                "/logs": {
  
                       "Source": "/home/server/mysql/logs",
  
                       "Destination": "/logs",
  
                       "RW": true,
  
                       "Name": "",
  
                       "Driver": "",
  
                       "Relabel": "",
  
                       "Propagation": "rprivate",
  
                       "Named": false,
  
                       "ID": ""
  
                },
  
                "/mysql_data": {
  
                       "Source": "/home/server/mysql/data",
  
                       "Destination": "/mysql_data",
  
                       "RW": true,
  
                       "Name": "",
  
                       "Driver": "",
  
                       "Relabel": "",
  
                       "Propagation": "rprivate",
  
                       "Named": false,
  
                       "ID": ""
  
                },
  
                "/var/lib/mysql": {
  
                       "Source": "",
  
                       "Destination": "/var/lib/mysql",
  
                       "RW": true,
  
                       "Name": "85d91bff7012b57606af819480ce267449084e81ab386737c80ace9fe75f6621",
  
                       "Driver": "local",
  
                       "Relabel": "",
  
                       "Propagation": "",
  
                       "Named": false,
  
                       "ID": "897cd0152dd152166cb2715044ca4a3915a1b66280e0eb096eb74c2d737d7f77"
  
                }
  
         },

  

• 启动docker服务

   sudo service docker start

• 启动所有docker容器

  sudo docker start $(docker ps -a | awk '{ print $1}' | tail -n +2)

修改docker默认的存储位置

---

docker 的所有images及相关信息存储位置为：/var/lib/docker

• 查看默认的docker存储路径

  docker info |grep 'Docker Root Dir'
  WARNING: No swap limit support
  Docker Root Dir: /var/lib/docker

• 停止所有docker容器

  sudo docker stop $(docker ps -a | awk '{ print $1}' | tail -n +2)

• 停止docker服务

  sudo service docker stop
  cd /var/lib

• 打包docker目录

  sudo tar -czvf /usr/docker.tar.gz docker/
  cd /usr/
  sudo tar -xzvf docker.tar.gz

• 修改docker默认的存储位置

  sudo vim /etc/docker/daemon.json
  
  {
      "graph": "/home/server/docker"
  }

• 启动docker服务

  sudo service docker start

• 启动所有docker容器

  sudo docker start $(docker ps -a | awk '{ print $1}' | tail -n +2)

• 查看修改后docker存储路径

  docker info |grep 'Docker Root Dir'
  WARNING: No swap limit support
  Docker Root Dir: /usr/docker
  
  本文转自：https://www.cnblogs.com/zhuochong/p/10070516.html ！！！！！！