dokcer的数据持久化
- docker提供三种方式将数据从宿主机挂载到容器中
开搞
volumes
[root@localhost ~]# docker ps -a #确认下当前有几个容器
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
be9a8ab117d1 nginx "/docker-entrypoint.…" 12 hours ago Exited (0) 11 hours ago web2
afb553ce70c8 nginx "/docker-entrypoint.…" 12 hours ago Exited (0) 11 hours ago web1
[root@localhost ~]# docker rm $(docker ps -aq) ##全部移除掉
be9a8ab117d1
afb553ce70c8
[root@localhost ~]# docker volume --help #查看volume命令帮助
Usage: docker volume COMMAND
Manage volumes
Commands:
create Create a volume #创建一个volume
inspect Display detailed information on one or more volumes #展现volume得详细信息
ls List volumes #列出volume
prune Remove all unused local volumes #移除不在使用得volume
rm Remove one or more volumes #移除一个或者多个volume
Run 'docker volume COMMAND --help' for more information on a command.
[root@localhost ~]# docker volume ls #查看当前有几个volume，很显然是没有得。
DRIVER VOLUME NAME
[root@localhost ~]# docker volume create web-vol #创建一个叫web-vol得volume
web-vol
[root@localhost ~]# docker volume ls #查看volume，发现有了刚刚创建的饿那个一个
DRIVER VOLUME NAME
local web-vol
[root@localhost ~]# docker run -d -v web-vol:/usr/share/nginx/html --name=web1 nginx #-v 将其挂载到新创建得容器，位置是nginx得网页目录位置
WARNING: IPv4 forwarding is disabled. Networking will not work.
fa7a8670d01e01e772abe3e256d0e3d2d309fceecc0e31763d1f33fb83da310b
[root@localhost ~]# docker ps #查看新创建得容器运行状况
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
fa7a8670d01e nginx "/docker-entrypoint.…" 34 seconds ago Up 31 seconds 80/tcp web1
[root@localhost ~]# docker volume inspect web-vol #查看volume得详细信息
[
{
"CreatedAt": "2021-03-05T11:48:27+08:00",
"Driver": "local",
"Labels": {},
"Mountpoint": "/var/lib/docker/volumes/web-vol/_data", #可以看到这个就是新创建得volume目录
"Name": "web-vol",
"Options": {},
"Scope": "local"
}
]
[root@localhost ~]# ls /var/lib/docker/volumes/web-vol/_data #可以很清楚得看见里面有nginx得网页文件
50x.html index.html
[root@localhost ~]# docker inspect fa7a8670d01e | grep -A 20 -i ipaddres #查看容器得ip地址
"SecondaryIPAddresses": null,
"SecondaryIPv6Addresses": null,
"EndpointID": "60f8343e40730166aa477b145474418597823acf100004b9e160adcf231c3306",
"Gateway": "172.17.0.1",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"IPAddress": "172.17.0.2",
"IPPrefixLen": 16,
"IPv6Gateway": "",
"MacAddress": "02:42:ac:11:00:02",
"Networks": {
"bridge": {
"IPAMConfig": null,
"Links": null,
"Aliases": null,
"NetworkID": "2cbcdbf497dd696ef1ea69839b941ddedc6aa6ee851d963d16282926d69f6da0",
"EndpointID": "60f8343e40730166aa477b145474418597823acf100004b9e160adcf231c3306",
"Gateway": "172.17.0.1",
"IPAddress": "172.17.0.2", #发现是172.17.0.1
"IPPrefixLen": 16,
"IPv6Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"MacAddress": "02:42:ac:11:00:02",
"DriverOpts": null
}
}
}
}
]
[root@localhost ~]# curl 172.17.0.2 #访问一下，成功访问
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
[root@localhost ~]# echo "hell0 word " > /var/lib/docker/volumes/web-vol/_data/index.html #在web-vol里面更改首页文件得内容
[root@localhost ~]# curl 172.17.0.2 #发现网站首页也是跟着变了
hell0 word
###上面得内容，是我们在创建了volume之后操作得，那么如果我们不创建volume，直接挂载呢，docker会自动创建volume嘛，答案是会的
[root@localhost ~]# docker run -d -v web-vol2:/usr/share/nginx/html --name=web2 nginx ##未创建volume，直接挂载
WARNING: IPv4 forwarding is disabled. Networking will not work.
7c81459329f0428c29bcbcdfc2ffc41eac7954af125b78b62116187091e485ac
[root@localhost ~]# docker volume ls #docker会自动创建的
DRIVER VOLUME NAME
local web-vol
local web-vol2
##接下来我们尝试一下，如果删除了容器，那么volume是否还会存在
[root@localhost ~]# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
7c81459329f0 nginx "/docker-entrypoint.…" About a minute ago Up About a minute 80/tcp web2
fa7a8670d01e nginx "/docker-entrypoint.…" 9 minutes ago Up 9 minutes 80/tcp web1
[root@localhost ~]# docker stop $(docker ps -aq) ##停止所有的容器
7c81459329f0
fa7a8670d01e
[root@localhost ~]# docker rm $(docker ps -aq) ##移除所有的容器
7c81459329f0
fa7a8670d01e
[root@localhost ~]# docker ps -a #当前没有容器了哈
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
[root@localhost ~]# docker volume ls #可以看到volume依然还在
DRIVER VOLUME NAME
local web-vol
local web-vol2
[root@localhost ~]# cat /var/lib/docker/volumes/web-vol/_data/index.html ##里面的内容依旧还有，是不是就达到了持久化了
hell0 word
###接下来，我们新建一个容器，直接挂载之前的那个volume
[root@localhost ~]# docker run -d -v web-vol:/usr/share/nginx/html --name=web3 nginx
WARNING: IPv4 forwarding is disabled. Networking will not work.
de1405111150972e226c6af3a2ba7fcecfef16c1efffcbfc8b35a0f83cd30216
[root@localhost ~]# docker inspect web3 | grep -A 20 -i ipaddres
"SecondaryIPAddresses": null,
"SecondaryIPv6Addresses": null,
"EndpointID": "6ebee48b42ec57de3ebf2a2e7f0ec635676f777ac182ff74338d03b34f68e762",
"Gateway": "172.17.0.1",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"IPAddress": "172.17.0.2",
"IPPrefixLen": 16,
"IPv6Gateway": "",
"MacAddress": "02:42:ac:11:00:02",
"Networks": {
"bridge": {
"IPAMConfig": null,
"Links": null,
"Aliases": null,
"NetworkID": "2cbcdbf497dd696ef1ea69839b941ddedc6aa6ee851d963d16282926d69f6da0",
"EndpointID": "6ebee48b42ec57de3ebf2a2e7f0ec635676f777ac182ff74338d03b34f68e762",
"Gateway": "172.17.0.1",
"IPAddress": "172.17.0.2",
"IPPrefixLen": 16,
"IPv6Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"MacAddress": "02:42:ac:11:00:02",
"DriverOpts": null
}
}
}
}
]
[root@localhost ~]# curl 172.17.0.2 #发现，新的容器挂载之前的那个volume也是可以的
hell0 word
[root@localhost ~]#bind mounts
[root@localhost ~]# mkdir vol #创建一个待挂载目录
[root@localhost ~]# docker run -d -v $PWD/vol:/usr/share/nginx/html --name=web4 nginx #创建一个新的容器，挂载我们刚刚的那个目录
WARNING: IPv4 forwarding is disabled. Networking will not work.
ddde61f54bfcdd442e6703a5378675be69d53c4b3919f64da5f2b45da087559d
[root@localhost ~]# docker inspect web4 | grep -i ipad -A 20
"SecondaryIPAddresses": null,
"SecondaryIPv6Addresses": null,
"EndpointID": "f2b7274f7c22261d0cce8b30d515da2627e3cdb4098f25f4bc68a47dc41e8802",
"Gateway": "172.17.0.1",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"IPAddress": "172.17.0.2",
"IPPrefixLen": 16,
"IPv6Gateway": "",
"MacAddress": "02:42:ac:11:00:02",
"Networks": {
"bridge": {
"IPAMConfig": null,
"Links": null,
"Aliases": null,
"NetworkID": "2cbcdbf497dd696ef1ea69839b941ddedc6aa6ee851d963d16282926d69f6da0",
"EndpointID": "f2b7274f7c22261d0cce8b30d515da2627e3cdb4098f25f4bc68a47dc41e8802",
"Gateway": "172.17.0.1",
"IPAddress": "172.17.0.2",
"IPPrefixLen": 16,
"IPv6Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"MacAddress": "02:42:ac:11:00:02",
"DriverOpts": null
}
}
}
}
]
[root@localhost ~]# curl 172.17.0.2 #访问403，应为我们的目录里面是空的
<html>
<head><title>403 Forbidden</title></head>
<body>
<center><h1>403 Forbidden</h1></center>
<hr><center>nginx/1.19.6</center>
</body>
</html>
[root@localhost ~]# echo 123 > vol/index.html #往目录里面写个index.html文件
[root@localhost ~]# curl 172.17.0.2 #发现可以正常的访问，说明这个挂载也是有效的
123
###接下来，我们尝试一下不创建目录，直接挂载一个不存在的目录，看看docker是否会帮我们创建
[root@localhost ~]# ls
nginx.tar vol web1.txt web2.txt
[root@localhost ~]# docker run -d -v $PWD/web:/usr/share/nginx/html --name=web5 nginx #挂载一个不存在的目录
WARNING: IPv4 forwarding is disabled. Networking will not work.
8fda22d309a755e53de2baa9dc0fd7d1e0f7cc5cd3a7940b3176e9e9b3befa84
[root@localhost ~]# ls
nginx.tar vol web web1.txt web2.txt #发现docker会帮我们创建所需要的目录
[root@localhost ~]# ls web #里面是空的
[root@localhost ~]# docker inspect web5 | grep -i ipad -A 20
"SecondaryIPAddresses": null,
"SecondaryIPv6Addresses": null,
"EndpointID": "2bcfeb6e07789c543b9c89aa8edf8aa092e0469b66f78b71593303921b3eaa5d",
"Gateway": "172.17.0.1",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"IPAddress": "172.17.0.3",
"IPPrefixLen": 16,
"IPv6Gateway": "",
"MacAddress": "02:42:ac:11:00:03",
"Networks": {
"bridge": {
"IPAMConfig": null,
"Links": null,
"Aliases": null,
"NetworkID": "2cbcdbf497dd696ef1ea69839b941ddedc6aa6ee851d963d16282926d69f6da0",
"EndpointID": "2bcfeb6e07789c543b9c89aa8edf8aa092e0469b66f78b71593303921b3eaa5d",
"Gateway": "172.17.0.1",
"IPAddress": "172.17.0.3", #得到容器的ip地址
"IPPrefixLen": 16,
"IPv6Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"MacAddress": "02:42:ac:11:00:03",
"DriverOpts": null
}
}
}
}
]
[root@localhost ~]# curl 172.17.0.3 #访问403
<html>
<head><title>403 Forbidden</title></head>
<body>
<center><h1>403 Forbidden</h1></center>
<hr><center>nginx/1.19.6</center>
</body>
</html>
[root@localhost ~]# echo 456 > web/index.html #创建首页文件
[root@localhost ~]# curl 172.17.0.3 #就可以发现能正常访问了
456结束
大家可以总结一下volume和bind mounts有什么区别，谢谢大家