docker 5 ：挂载的方式

docker的挂载分为：

1. 绝对路径挂载
2. 匿名挂载
3. 具名挂载
4. DockerFile挂载

docker挂载的磁盘有一个默认的路径，也可以手动指定绝对路径完成挂载。

默认的挂载路径为：/var/lib/docker/volumes/

若为匿名挂载就是在挂载的时候，不指定挂载磁盘的名称，这样磁盘的名称将会有一串随机数代替。

[root@localhost data]# docker run -d -P --name nginx01 -v /etc/nginx nginx
2cb05e153b0982a647ad80eea8cef52332c17f442e81eb4e0051ce19624d1cb5

参数说明：
-P：随机端口映射
-v：这里没有指定宿主机磁盘的名称，则会产生随机名称。

[root@localhost data]# docker volume ls     #查看挂载的磁盘
DRIVER    VOLUME NAME
local     0f175a688227543ae22a470054c1da2d93376277da68387608f421f5a16bee43
local     1e8b4ce6d61660e8e95e946fc5b14786aa2f8daafa0135d4be5c0ed731caa6d6

通过命令可以看到具体的路径：
[root@localhost _data]# docker volume inspect 1e8b4ce6d61660e8e95e946fc5b14786aa2f8daafa0135d4be5c0ed731caa6d6 
[
    {
        "CreatedAt": "2021-04-01T00:43:07-04:00",
        "Driver": "local",
        "Labels": null,
        "Mountpoint": "/var/lib/docker/volumes/1e8b4ce6d61660e8e95e946fc5b14786aa2f8daafa0135d4be5c0ed731caa6d6/_data",
        "Name": "1e8b4ce6d61660e8e95e946fc5b14786aa2f8daafa0135d4be5c0ed731caa6d6",
        "Options": null,
        "Scope": "local"
    }
]

　　若挂载的时候指定名称，则名具名挂载。参考如下：

[root@localhost data]# docker run -d -P --name nginx02 -v test-nginx:/etc/nginx nginx
f132a2edcf332c80a3a74945162115d9169918f94e80407a396352cf617116bb

参数说明：
-v：这里指定了名称，但是不是一个绝对路径，所以仍然会放在默认位置。

[root@localhost data]# docker ps
CONTAINER ID   IMAGE                 COMMAND                  CREATED             STATUS             PORTS                               NAMES
f132a2edcf33   nginx                 "/docker-entrypoint.…"   4 seconds ago       Up 2 seconds       0.0.0.0:49154->80/tcp               nginx02
2cb05e153b09   nginx                 "/docker-entrypoint.…"   53 seconds ago      Up 51 seconds      0.0.0.0:49153->80/tcp               nginx01
440a5df74aa3   mysql:5.7             "docker-entrypoint.s…"   About an hour ago   Up About an hour   33060/tcp, 0.0.0.0:3310->3306/tcp   mysql01
3cf493d3feb0   portainer/portainer   "/portainer"             18 hours ago        Up 18 hours        0.0.0.0:8088->9000/tcp              clever_kowalevski

[root@localhost data]# docker volume ls
DRIVER    VOLUME NAME
local     0f175a688227543ae22a470054c1da2d93376277da68387608f421f5a16bee43
local     1e8b4ce6d61660e8e95e946fc5b14786aa2f8daafa0135d4be5c0ed731caa6d6
local     test-nginx

[root@localhost data]# docker volume inspect test-nginx 
[
    {
        "CreatedAt": "2021-04-01T00:43:56-04:00",
        "Driver": "local",
        "Labels": null,
        "Mountpoint": "/var/lib/docker/volumes/test-nginx/_data",
        "Name": "test-nginx",
        "Options": null,
        "Scope": "local"
    }
]

[root@localhost data]# cd /var/lib/docker/volumes/test-nginx/_data
[root@localhost _data]# ll
total 36
drwxr-xr-x. 2 root root   26 Apr  1 00:43 conf.d
-rw-r--r--. 1 root root 1007 Mar 30 10:47 fastcgi_params
-rw-r--r--. 1 root root 2837 Mar 30 10:47 koi-utf
-rw-r--r--. 1 root root 2223 Mar 30 10:47 koi-win
-rw-r--r--. 1 root root 5231 Mar 30 10:47 mime.types
lrwxrwxrwx. 1 root root   22 Mar 30 10:58 modules -> /usr/lib/nginx/modules
-rw-r--r--. 1 root root  643 Mar 30 10:58 nginx.conf
-rw-r--r--. 1 root root  636 Mar 30 10:47 scgi_params
-rw-r--r--. 1 root root  664 Mar 30 10:47 uwsgi_params
-rw-r--r--. 1 root root 3610 Mar 30 10:47 win-utf

　　挂载的时候可以限制容器的权限：

[root@localhost volumes]# docker run -d -P --name nginx03 -v test-nginx:/etc/nginx:ro nginx
73158e359693547285686bcea7e291194081500bd1124ef6ca56ef30261ed017

参数说明：
-v： test-nginx:/etc/nginx:ro后面的ro描述readonly，也可以为rw。

　　另外在build镜像的时候也可以挂载。也就是dockfile挂载。我们build一个镜像试试。

进入/home创建DockerFile/目录，然后创建dockerfile1，并编写写入响应代码：
[root@localhost ~]# cd /home
[root@localhost home]# mkdir DockerFile
[root@localhost home]# cd DockerFile/
[root@localhost DockerFile]# vi dockerfile1
FROM centos      #镜像源
VOLUME ["/dataVolume1","/dataVolume2"]     #挂载的磁盘
CMD echo "-----success-----"    #返回值
CMD /bin/bash        #返回值

[root@localhost DockerFile]# docker build -f /home/DockerFile/dockerfile1 -t volume1/centos .
Sending build context to Docker daemon  2.048kB
Step 1/4 : FROM centos
 ---> 300e315adb2f
Step 2/4 : VOLUME ["/dataVolume1","/dataVolume2"]
 ---> Running in 2886725e8302
Removing intermediate container 2886725e8302
 ---> 3d4aa9506a3d
Step 3/4 : CMD echo "-----success-----"
 ---> Running in 5c38936cd6b1
Removing intermediate container 5c38936cd6b1
 ---> b0443a9eb581
Step 4/4 : CMD /bin/bash
 ---> Running in 10b48f6b766e
Removing intermediate container 10b48f6b766e
 ---> 04b2be41fc6c
Successfully built 04b2be41fc6c
Successfully tagged volume1/centos:latest

参数说明：
-f：后面跟DockerFile的名称
-t：创建的镜像的名称
.：表示创建镜像的时候发送给docker守护进程的文件所在的文件夹，.表示当前文件夹。

查看镜像：
[root@localhost ~]# docker images
REPOSITORY            TAG       IMAGE ID       CREATED        SIZE
volume1/centos        latest    04b2be41fc6c   2 hours ago    209MB
nginx                 latest    7ce4f91ef623   28 hours ago   133MB
mysql                 5.7       cd0f0b1e283d   28 hours ago   449MB
portainer/portainer   latest    580c0e4e98b0   13 days ago    79.1MB
centos                latest    300e315adb2f   3 months ago   209MB
centos                centos7   8652b9f0cb4c   4 months ago   204MB

以创建的镜像运行一个容器：
发现在根目录下多出来两个文件夹，datavolume1和datavolume2,这两个为我们在DockerFile中定义的挂载磁盘。
[root@localhost ~]# docker run -it volume1/centos /bin/bash
[root@7f4057c4dde2 /]# ls -l
total 0
lrwxrwxrwx.   1 root root   7 Nov  3 15:22 bin -> usr/bin
drwxr-xr-x.   2 root root   6 Apr  1 09:19 dataVolume1
drwxr-xr-x.   2 root root   6 Apr  1 09:19 dataVolume2
drwxr-xr-x.   5 root root 360 Apr  1 09:19 dev
drwxr-xr-x.   1 root root  66 Apr  1 09:19 etc
drwxr-xr-x.   2 root root   6 Nov  3 15:22 home
lrwxrwxrwx.   1 root root   7 Nov  3 15:22 lib -> usr/lib
lrwxrwxrwx.   1 root root   9 Nov  3 15:22 lib64 -> usr/lib64
drwx------.   2 root root   6 Dec  4 17:37 lost+found
drwxr-xr-x.   2 root root   6 Nov  3 15:22 media
drwxr-xr-x.   2 root root   6 Nov  3 15:22 mnt
drwxr-xr-x.   2 root root   6 Nov  3 15:22 opt
dr-xr-xr-x. 148 root root   0 Apr  1 09:19 proc
dr-xr-x---.   2 root root 162 Dec  4 17:37 root
drwxr-xr-x.  11 root root 163 Dec  4 17:37 run
lrwxrwxrwx.   1 root root   8 Nov  3 15:22 sbin -> usr/sbin
drwxr-xr-x.   2 root root   6 Nov  3 15:22 srv
dr-xr-xr-x.  13 root root   0 Mar 31 13:52 sys
drwxrwxrwt.   7 root root 145 Dec  4 17:37 tmp
drwxr-xr-x.  12 root root 144 Dec  4 17:37 usr
drwxr-xr-x.  20 root root 262 Dec  4 17:37 var

查看运行容器的详情，可以看到挂载的磁盘对应的宿主机文件夹路径。

[root@localhost ~]# docker inspect 7f4057c4dde2
"Mounts": [
            {
                "Type": "volume",
                "Name": "6cf761970000f3bded19825f7e9c657fb3d46182e4eca3082e974126b66d1083",
                "Source": "/var/lib/docker/volumes/6cf761970000f3bded19825f7e9c657fb3d46182e4eca3082e974126b66d1083/_data",
                "Destination": "/dataVolume1",
                "Driver": "local",
                "Mode": "",
                "RW": true,
                "Propagation": ""
            },
            {
                "Type": "volume",
                "Name": "679f5fc2b9d444a3e5abce6ee30b00f1e9582aad833c6a602ed02369facad144",
                "Source": "/var/lib/docker/volumes/679f5fc2b9d444a3e5abce6ee30b00f1e9582aad833c6a602ed02369facad144/_data",
                "Destination": "/dataVolume2",
                "Driver": "local",
                "Mode": "",
                "RW": true,
                "Propagation": ""
            }
通过如下明了也可以看到多了两个匿名挂载：
[root@localhost ~]# docker volume ls
DRIVER    VOLUME NAME
local     0f175a688227543ae22a470054c1da2d93376277da68387608f421f5a16bee43
local     1e8b4ce6d61660e8e95e946fc5b14786aa2f8daafa0135d4be5c0ed731caa6d6
local     6cf761970000f3bded19825f7e9c657fb3d46182e4eca3082e974126b66d1083
local     679f5fc2b9d444a3e5abce6ee30b00f1e9582aad833c6a602ed02369facad144

然后回到宿主机，进入到对应挂载的目录下创建1.txt文件，可以看到容器中也可以看到该文件。
[root@localhost ~]# cd /var/lib/docker/volumes/6cf761970000f3bded19825f7e9c657fb3d46182e4eca3082e974126b66d1083/_data
[root@localhost _data]# touch 1.txt

[root@7f4057c4dde2 /]# ls dataVolume1
1.txt