【Docker】docker日常工作总结（涉及基础命令、基础名词概念、镜像、容器、网络、数据卷）
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前提：必须有一个docker环境，可以安装到windows、linux、Ubuntu；博主是安装到ubuntu中的。具体安装步骤可以借鉴https://blog.csdn.net/YZL40514131/article/details/124486645这篇文章
一、镜像和容器
提示
在docker中把安装包叫做镜像
镜像是启动一个服务的时候所有的配置文件
容器是运行镜像后的一个状态，容器才是真正提供业务的单位
1、查看ubuntu中所有的镜像
sudo docker images
sudo docker image ls
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
nginx latest 0e901e68141f 4 days ago 142MB
jenkins/jenkins lts cb535f2a7054 5 days ago 464MB
nginx alpine b1c3acb28882 2 weeks ago 23.4MB
mysql 8.0.29 96d0eae5ed60 4 weeks ago 524MB
mysql latest 96d0eae5ed60 4 weeks ago 524MB
hello-world latest feb5d9fea6a5 8 months ago 13.3kB
centos latest 5d0da3dc9764 8 months ago 231MB
delron/fastdfs latest 8487e86fc6ee 4 years ago 464MB
delron/elasticsearch-ik 2.4.6-1.0 095b6487fb77 4 years ago 689MB
morunchang/fastdfs latest a729ac95698a 5 years ago 460MB
2、删除镜像
报错的原因是：nginx正在运行中，不能删除
sudo docker image rm nginx:alpine(镜像名称 ：镜像tag)
sudo docker rmi 0e901e68141f（镜像id）
sudo docker image rm 0e901e68141f（镜像id）
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker image rm nginx:alpine
Error response from daemon: conflict: unable to remove repository reference "nginx" (must force) - container d992bc0fa330 is using its referenced image 0e901e68141f
解决：强制删除（-f：强制删除）
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker image rm -f nginx:alpine
3、查看镜像的历史记录
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker history nginx
4、下载镜像
1、sudo docker search redis：查看镜像相关的安装包（例如查看redis相关的安装包，建议使用官方的安装包）
2、也可以百度docker hub去获取相关的安装包https://registry.hub.docker.com/
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker search redis
NAME DESCRIPTION STARS OFFICIAL AUTOMATED
redis Redis is an open source key-value store that… 10992 [OK]
bitnami/redis Bitnami Redis Docker Image 220 [OK]
bitnami/redis-sentinel Bitnami Docker Image for Redis Sentinel 37 [OK]
bitnami/redis-cluster 32
rapidfort/redis RapidFort optimized, hardened image for Redi… 14
rapidfort/redis-cluster RapidFort optimized, hardened image for Redi… 14
circleci/redis CircleCI images for Redis 13 [OK]
ubuntu/redis Redis, an open source key-value store. Long-… 10
bitnami/redis-exporter 7
clearlinux/redis Redis key-value data structure server with t… 4
google/guestbook-python-redis A simple guestbook example written in Python… 4
ibmcom/redis-ha 1
bitnami/redis-sentinel-exporter 1
ibmcom/ibm-cloud-databases-redis-operator Container image for the IBM Operator for Red… 1
ibmcom/ibm-cloud-databases-redis-operator-bundle Bundle image for the IBM Operator for Redis 1
ibmcom/ibm-cloud-databases-redis-catalog Catalog image for the IBM Operator for Redis 1
ibmcom/redis-ppc64le 0
blackflysolutions/redis Redis container for Drupal and CiviCRM 0
ibmcom/redisearch-ppc64le 0
drud/redis redis 0 [OK]
rancher/redislabs-ssl 0
vmware/redis-photon 0
cimg/redis 0
newrelic/k8s-nri-redis New Relic Infrastructure Redis Integration (… 0
astronomerinc/ap-redis Redis service for Airflow's celery executor … 0
5、拉取镜像
如果在拉取镜像时没有指定版本号，默认拉取的是最新的，例如sudo docker pull python
例如：拉取指定的版本：sudo docker pull mysql：5.7
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker pull python
Using default tag: latest
latest: Pulling from library/python
e756f3fdd6a3: Pull complete
bf168a674899: Pull complete
e604223835cc: Pull complete
6d5c91c4cd86: Pull complete
2cc8d8854262: Pull complete
2767dbfeeb87: Pull complete
e5f27d860d89: Pull complete
98a3e4f5f5ed: Pull complete
af265a3ad3e0: Pull complete
Digest: sha256:bef6fd726fb8825d5cf26933d8477505b14505be1a98394405c8840c1c266bdd
Status: Downloaded newer image for python:latest
docker.io/library/python:latest
6、查看镜像的详细信息
sudo docker inspect python:latest(镜像名：tag)
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker inspect python:latest
7、查看容器：
sudo docker ps：查看正在运行的容器
sudo docker ps -a：查看所有的容器
sudo docker container ls：查看正在运行的容器
sudo docker container ls --all ：查看所有的容器
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker container ls
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
bca70facba90 nginx:alpine "/docker-entrypoint.…" 3 hours ago Up 3 hours 0.0.0.0:49160->80/tcp, :::49160->80/tcp web4
ff2d3c951eed nginx:alpine "/docker-entrypoint.…" 3 hours ago Up 3 hours 0.0.0.0:49159->80/tcp, :::49159->80/tcp web3
4011f219f403 nginx:alpine "/docker-entrypoint.…" 3 hours ago Up 3 hours 0.0.0.0:49158->80/tcp, :::49158->80/tcp web2
d992bc0fa330 nginx "/docker-entrypoint.…" 3 hours ago Up 3 hours 80/tcp nginx_test
2c4108268aa9 jenkins/jenkins:lts "/sbin/tini -- /usr/…" 25 hours ago Up 25 hours 0.0.0.0:49154->8080/tcp, :::49154->8080/tcp, 0.0.0.0:49153->50000/tcp, :::49153->50000/tcp jenkins
ae1fd6dd1b00 mysql "docker-entrypoint.s…" 3 weeks ago Up 3 days 0.0.0.0:3306->3306/tcp, :::3306->3306/tcp, 33060/tcp mysql
8、运行容器
1、sudo docker run redis：redis是一个镜像，首先去本地查看有没有redis的镜像，如果有直接去运行，如果没有，默认去docker hub官方镜像中拉取到本地
2、如果后面没有指名版本号，等价于sudo docker run redis:latest(最新的)
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker run redis
Unable to find image 'redis:latest' locally
latest: Pulling from library/redis
42c077c10790: Already exists
a300d83d65f9: Pull complete
ebdc3afaab5c: Pull complete
31eec7f8651c: Pull complete
9c6a6b89d274: Pull complete
5c8099a4b45c: Pull complete
Digest: sha256:1b90dbfe6943c72a7469c134cad3f02eb810f016049a0e19ad78be07040cdb0c
Status: Downloaded newer image for redis:latest
1:C 02 Jun 2022 05:36:13.616 # oO0OoO0OoO0Oo Redis is starting oO0OoO0OoO0Oo
1:C 02 Jun 2022 05:36:13.616 # Redis version=7.0.0, bits=64, commit=00000000, modified=0, pid=1, just started
1:C 02 Jun 2022 05:36:13.616 # Warning: no config file specified, using the default config. In order to specify a config file use redis-server /path/to/redis.conf
1:M 02 Jun 2022 05:36:13.616 * monotonic clock: POSIX clock_gettime
1:M 02 Jun 2022 05:36:13.617 * Running mode=standalone, port=6379.
1:M 02 Jun 2022 05:36:13.617 # Server initialized
1:M 02 Jun 2022 05:36:13.617 # WARNING overcommit_memory is set to 0! Background save may fail under low memory condition. To fix this issue add 'vm.overcommit_memory = 1' to /etc/sysctl.conf and then reboot or run the command 'sysctl vm.overcommit_memory=1' for this to take effect.
1:M 02 Jun 2022 05:36:13.618 * The AOF directory appendonlydir doesn't exist
1:M 02 Jun 2022 05:36:13.618 * Ready to accept connections
^C1:signal-handler (1654148179) Received SIGINT scheduling shutdown...
1:M 02 Jun 2022 05:36:19.649 # User requested shutdown...
1:M 02 Jun 2022 05:36:19.649 * Saving the final RDB snapshot before exiting.
1:M 02 Jun 2022 05:36:19.649 * DB saved on disk
1:M 02 Jun 2022 05:36:19.649 # Redis is now ready to exit, bye bye...
默认运行一个容器时容器名称是随机生成的
运行的时候指定容器名称，容器名称必须唯一
- -name ：给容器指定名称
- -name与容器名称在一块，不能分开
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker run --name centos_t1 centos
-it：运行容器，并且进入容器中
退出容器：exit
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker run -it --name centos_t2 centos
[root@90f0e8d75990 /]#
✨例如：进入到centos容器中了
选择tag，建议使用alpine：非常小
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker run --name nginx_1 nginx
/docker-entrypoint.sh: /docker-entrypoint.d/ is not empty, will attempt to perform configuration
/docker-entrypoint.sh: Looking for shell scripts in /docker-entrypoint.d/
/docker-entrypoint.sh: Launching /docker-entrypoint.d/10-listen-on-ipv6-by-default.sh
10-listen-on-ipv6-by-default.sh: info: Getting the checksum of /etc/nginx/conf.d/default.conf
10-listen-on-ipv6-by-default.sh: info: Enabled listen on IPv6 in /etc/nginx/conf.d/default.conf
/docker-entrypoint.sh: Launching /docker-entrypoint.d/20-envsubst-on-templates.sh
/docker-entrypoint.sh: Launching /docker-entrypoint.d/30-tune-worker-processes.sh
/docker-entrypoint.sh: Configuration complete; ready for start up
2022/06/02 05:58:04 [notice] 1#1: using the "epoll" event method
2022/06/02 05:58:04 [notice] 1#1: nginx/1.21.6
2022/06/02 05:58:04 [notice] 1#1: built by gcc 10.2.1 20210110 (Debian 10.2.1-6)
2022/06/02 05:58:04 [notice] 1#1: OS: Linux 5.13.0-40-generic
2022/06/02 05:58:04 [notice] 1#1: getrlimit(RLIMIT_NOFILE): 1048576:1048576
2022/06/02 05:58:04 [notice] 1#1: start worker processes
2022/06/02 05:58:04 [notice] 1#1: start worker process 31
2022/06/02 05:58:04 [notice] 1#1: start worker process 32
2022/06/02 05:58:04 [notice] 1#1: start worker process 33
2022/06/02 05:58:04 [notice] 1#1: start worker process 34
2022/06/02 05:58:06 [notice] 1#1: signal 28 (SIGWINCH) received
宿主机（ubuntu）的端口映射容器端口（访问宿主机中的1111端口相当于访问容器中的80端口）
-p：手动指定端口
-P：不需要手动指定端口，会随机的指定端口
✨例如启动nginx手动指定端口
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker run --name nginx_2 -p 1111:80 nginx
/docker-entrypoint.sh: /docker-entrypoint.d/ is not empty, will attempt to perform configuration
/docker-entrypoint.sh: Looking for shell scripts in /docker-entrypoint.d/
/docker-entrypoint.sh: Launching /docker-entrypoint.d/10-listen-on-ipv6-by-default.sh
10-listen-on-ipv6-by-default.sh: info: Getting the checksum of /etc/nginx/conf.d/default.conf
10-listen-on-ipv6-by-default.sh: info: Enabled listen on IPv6 in /etc/nginx/conf.d/default.conf
/docker-entrypoint.sh: Launching /docker-entrypoint.d/20-envsubst-on-templates.sh
/docker-entrypoint.sh: Launching /docker-entrypoint.d/30-tune-worker-processes.sh
/docker-entrypoint.sh: Configuration complete; ready for start up
2022/06/02 06:06:19 [notice] 1#1: using the "epoll" event method
2022/06/02 06:06:19 [notice] 1#1: nginx/1.21.6
2022/06/02 06:06:19 [notice] 1#1: built by gcc 10.2.1 20210110 (Debian 10.2.1-6)
2022/06/02 06:06:19 [notice] 1#1: OS: Linux 5.13.0-40-generic
2022/06/02 06:06:19 [notice] 1#1: getrlimit(RLIMIT_NOFILE): 1048576:1048576
2022/06/02 06:06:19 [notice] 1#1: start worker processes
2022/06/02 06:06:19 [notice] 1#1: start worker process 32
2022/06/02 06:06:19 [notice] 1#1: start worker process 33
2022/06/02 06:06:19 [notice] 1#1: start worker process 34
2022/06/02 06:06:19 [notice] 1#1: start worker process 35
^C2022/06/02 06:07:31 [notice] 1#1: signal 2 (SIGINT) received, exiting
2022/06/02 06:07:31 [notice] 33#33: exiting
2022/06/02 06:07:31 [notice] 34#34: exiting
2022/06/02 06:07:31 [notice] 32#32: exiting
2022/06/02 06:07:31 [notice] 35#35: exiting
2022/06/02 06:07:31 [notice] 34#34: exit
2022/06/02 06:07:31 [notice] 33#33: exit
2022/06/02 06:07:31 [notice] 32#32: exit
2022/06/02 06:07:31 [notice] 35#35: exit
2022/06/02 06:07:31 [notice] 1#1: signal 17 (SIGCHLD) received from 35
2022/06/02 06:07:31 [notice] 1#1: worker process 32 exited with code 0
2022/06/02 06:07:31 [notice] 1#1: worker process 35 exited with code 0
2022/06/02 06:07:31 [notice] 1#1: signal 29 (SIGIO) received
2022/06/02 06:07:31 [notice] 1#1: signal 17 (SIGCHLD) received from 33
2022/06/02 06:07:31 [notice] 1#1: worker process 33 exited with code 0
2022/06/02 06:07:31 [notice] 1#1: signal 29 (SIGIO) received
2022/06/02 06:07:31 [notice] 1#1: signal 17 (SIGCHLD) received from 34
2022/06/02 06:07:31 [notice] 1#1: worker process 34 exited with code 0
2022/06/02 06:07:31 [notice] 1#1: exit
✨小写p：宿主机访问1111端口
✨大写P：宿主机访问49161端口（随机指定的）
目前存在的问题：1、启动nginx，终端会展示日志；2、一旦关闭终端，容器将停止工作。
解决：
9、后台运行容器
-d：指定容器在后台执行
特别注意：如果是手动指定端口，需要将防火墙中的这个端口放通
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker run --name nginx_4 -P -d nginx
fa855451e519418cf4348a16dcaf52dcbd53e971bc934e196bdb3130acd72026
- -rm：退出容器后，会自动将容器删除
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker run -it --name centos_1 --rm centos
[root@f992808f12cc /]# exit
exit
10、创建容器的时候指定环境变量
-e：设置全局变量
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker run --rm -it -e USERNAME=kobe -e PASSWORD=123123 centos /bin/bash
[root@0489627cb70f /]# env
LANG=en_US.UTF-8
HOSTNAME=0489627cb70f
USERNAME=kobe
PASSWORD=123123
PWD=/
HOME=/root
TERM=xterm
SHLVL=1
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
LESSOPEN=||/usr/bin/lesspipe.sh %s
_=/usr/bin/env
11、进入正在运行中的容器
exec：进入正在运行中的容器
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker exec -it centos_1 /bin/bash
[root@7e1cf2a4bec7 /]#
✨当容器太多时，查看需要的容器
zhilong@zhilong-virtual-machine:~/桌面$ sudo docker ps | awk '/Up/ {print $1,$NF}'
95cf126972d5 centos_2
7e1cf2a4bec7 centos_1
d992bc0fa330 nginx_test
2c4108268aa9 jenkins
ae1fd6dd1b00 mysql
12、查看某个容器的进程
zhilong@zhilong-virtual-machine:~/桌面$ sudo docker top centos_1
UID PID PPID C STIME TTY TIME CMD
root 52297 52276 0 14:31 pts/0 00:00:00 /bin/bash
zhilong@zhilong-virtual-machine:~/桌面$
13、查看容器资源利用率
CONTAINER ID NAME CPU % MEM USAGE / LIMIT MEM % NET I/O BLOCK I/O PIDS
7e1cf2a4bec7 centos_1 0.00% 2.566MiB / 3.798GiB 0.07% 3.79kB / 0B 1.43MB / 0B 1
停止容器：sudo docker stop 容器id或者容器名称
重启容器：sudo docker restart 容器id或者容器名称
暂停容器：sudo docker paush 容器id或者容器名称
取消暂停容器：sudo docker unpaush 容器id或者容器名称
删除容器：sudo docker rm 容器id或者容器名称(前提是先暂停容器)
强制删除容器：sudo docker rm -f 容器id或者容器名称
二、网络
1、网络类型：
✨bridge：
-
nat网络模型
-
虚拟交换机
✨host
-
与宿主机共享网络
-
–net=host
✨none
-
不配置网络
-
–net=none
✨overlay
- 不同网络进行通信
2、查看容器的ip地址
sudo docker inspect nginx_1：查看容器的详细信息
sudo docker exec -it nginx_1 ip a：进入容器查看容器的ip
172.17.0.5
✨第一种方法：
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker exec -it nginx_1 ip a
1: lo: ,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
112: eth0@if113: ,MULTICAST,UP,LOWER_UP,M-DOWN> mtu 1500 qdisc noqueue state UP
link/ether 02:42:ac:11:00:05 brd ff:ff:ff:ff:ff:ff
inet 172.17.0.5/16 brd 172.17.255.255 scope global eth0
valid_lft forever preferred_lft forever
✨第二方法：
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker inspect nginx_1 | grep "IPAddress"
"SecondaryIPAddresses": null,
"IPAddress": "172.17.0.5",
"IPAddress": "172.17.0.5",
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker inspect nginx_2 | grep "IPAddress"
"SecondaryIPAddresses": null,
"IPAddress": "172.17.0.6",
"IPAddress": "172.17.0.6",
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker inspect nginx_3 | grep "IPAddress"
"SecondaryIPAddresses": null,
"IPAddress": "172.17.0.7",
"IPAddress": "172.17.0.7",
✨查看nginx_1、nginx_2、nginx_3三个容器的ip地址
查看nginx_1、nginx_2、nginx_3三个容器的网关地址，得到结论：用sudo docker run创建的容器会默认挂载到docker0上面，docker0作为一个桥梁进行上网。所以可以上外网
3、创建网络：默认指定的网关地址和子网地址
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker network create -d bridge mynet2
80a7f08272dde3d0b7dd7a91b67b823415e554dd5d8bae8bee0293697b055680
✨查看详情
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker network inspect mynet2
[
{
"Name": "mynet2",
"Id": "80a7f08272dde3d0b7dd7a91b67b823415e554dd5d8bae8bee0293697b055680",
"Created": "2022-06-02T19:44:30.465164936+08:00",
"Scope": "local",
"Driver": "bridge",
"EnableIPv6": false,
"IPAM": {
"Driver": "default",
"Options": {},
"Config": [
{
"Subnet": "172.20.0.0/16",
"Gateway": "172.20.0.1"
}
]
},
"Internal": false,
"Attachable": false,
"Ingress": false,
"ConfigFrom": {
"Network": ""
},
"ConfigOnly": false,
"Containers": {},
"Options": {},
"Labels": {}
}
]
4、创建网络：手动指定网关
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker network create -d bridge --subnet 172.16.200.0/24 mynet3
0e062b2fd2340178cc7e6fc72377418314236f9f2be826cb504d45e18be124da
使用sudo docker run 创建的容器会默认加入到docker0桥接网络里面，这个桥接网络里面是不支持通过容器的名字去访问的；
但是我们自己创建的桥接网络，除了可以使用ip地址去访问以外，还可以通过容器名称去访问。
5、删除网络
sudo docker network rm 网络
如果容器正在启动中，不能直接删除网络，需要先将容器删除，再删除网络
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker network rm mynet1
[sudo] zhilong 的密码：
mynet1
sudo docker network prune：把无用的网络删除
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/docker$ sudo docker network prune
WARNING! This will remove all custom networks not used by at least one container.
Are you sure you want to continue? [y/N] y
Deleted Networks:
mynet
mynet2
mynet3
三、Volume
实现容器和宿主机之间的数据共享
1、介绍
使用数据卷实现数据持久化
数据备份、数据共享
将宿主机中的目录和容器中的目录进行映射
将宿主机中的文件和容器中的文件进行映射
将数据卷与容器中的目录进行映射
2、例如将目录“/home/zhilong/Desktop/shell_text”与容器中的目录做映射
-v：映射
如果冒号左边的目录或者文件不存在，会自动创建数据卷，通过sudo docker volume ls查看
sudo docker inspect 数据卷名称：查看数据卷的详细信息
可以查看数据卷的路径：/var/lib/docker/volumes/数据卷名称/_data
zhilong@zhilong-virtual-machine:~/Desktop/shell_text$ sudo docker run --name nginx_02 -d -P -v /home/zhilong/Desktop/shell_text/nginx_test:/usr/share/nginx/html/ nginx:alpine
42ea2b7b22f51ff6f43de6362b1b81c4112e3ddf155e4c0f100c9b33acd09cbd
3、在宿主机的nginx_test目录下创建一个index.html文件，通过容器去访问
进入容器中，可以看到和宿主机中有一样的文件
zhilong@zhilong-virtual-machine:~/Desktop/shell_text$ sudo docker exec -it nginx_02
"docker exec" requires at least 2 arguments.
See 'docker exec --help'.
Usage: docker exec [OPTIONS] CONTAINER COMMAND [ARG...]
Run a command in a running container
zhilong@zhilong-virtual-machine:~/Desktop/shell_text$ sudo docker exec -it nginx_02 /bin/sh
/ # cd /usr/share/nginx/html
/usr/share/nginx/html # ls
6.html index.html
/usr/share/nginx/html #
在容器的/usr/share/nginx/html/目录下创建文件，也可以到宿主机中看到；容器中的目录、文件和宿主机中的文件和目录是一致的。
可以在宿主机中动态的修改文件，容器中可以动态的识别文件
4、假如nginx_1容器挂掉了，去创建一个新的容器nginx_2，同样做映射，数据并不会丢
5、创建数据卷
sudo docker volume create 数据卷
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/nginx_test$ sudo docker volume create v1
v1
6、删除数据卷
sudo docker volume rm 数据卷
zhilong@zhilong-virtual-machine:~/Desktop/shell_text/nginx_test$ sudo docker volume rm v101
Error: No such volume: v101
7、删除没用的数据卷
sudo docker volume prune
