Using data volume, the database can guarantee that if the container there is a problem but the data is not lost role, such as data in MySQL / date
index.html in the root directory or Nginx
View data volumes
[root@docker ~]# docker volume ls
DRIVER VOLUME NAME
Create a data volume
[root@docker ~]# docker volume create nginx-vol
nginx-vol
View have created a group called nginx-vol data volumes
[root@docker ~]# docker volume ls
DRIVER VOLUME NAME
local nginx-vol
For more information see data volumes
[root@docker ~]# docker volume inspect nginx-vol
Running a call nginx-test container and mount the data volume, source directory nginx-vol target directory Nginx of html the root page
[root@docker ~]# docker run -itd --name nginx-test --mount src=nginx-vol,dst=/usr/share/nginx/html nginx
8ea39f5eb3fac2d85039314117985abd5f6393548a0eb45e27946c424ebebfe8
To the web directory View
[root@docker ~]# docker exec -it nginx-test bash
root@8ea39f5eb3fa:/# cd /usr/share/nginx/html/
root@8ea39f5eb3fa:/usr/share/nginx/html# ls
50x.html index.html
To mount the directory to see if there are already a data volume
[root@docker ~]# cd /var/lib/docker/volumes/
[root@docker volumes]# ls
metadata.db nginx-vol
[root@docker volumes]# cd nginx-vol/
[root@docker nginx-vol]# ls
_data
[root@docker nginx-vol]# cd _data/
[root@docker _data]# ls
50x.html index.html
Delete all container to view the database there
[root@docker ~]# docker rm -f $(docker container ls -qa)
8ea39f5eb3fa
5deb5f032783
4c6e1ee32733
[root@docker volumes]# cd nginx-vol/_data/
[root@docker _data]# ls
50x.html index.html
In just run a container and specify the port mapping
[root@docker _data]# docker run -itd --name nginx-test -p 89:80 --mount src=nginx-vol,dst=/usr/share/nginx/html nginx
6f6a742b02272b1eff38974e633e84033f257d6e1b8097c4b60202f1d3b6c451
In the data volume directory and create a a.html file viewing, here it is to play the role of persistent data volumes mounted
[root@docker _data]# curl 192.168.30.22:89
23456
[root@docker _data]# vim a.html
[root@docker _data]# curl 192.168.30.22:89/a.html
<h1>hello</h1>
I switched to add a port mapping, so imagine if you start 100 of such containers, are using this data volumes, scalability is very strong, but different ports
[root@docker ~]# docker run -itd --name nginx-test2 -p 90:80 --mount src=nginx-vol,dst=/usr/share/nginx/html nginx
8e3f213e652b31daef38f169240d2388386afeada29ff3367e712ccc98163f49
[root@docker _data]# curl 192.168.30.22:90
23456
[root@docker _data]# curl 192.168.30.22:90/a.html
<h1>hello</h1>