Technical work, should be praised and then see, form a habitCopy the codeDocker use tutorial related series of directories
Volumes are introduced
The data volume provides the following functions: When the container fails, the actual directory of the data volume is stored on the host. Data will not be lost. Starting a new container does not affect data as long as the data volume still exists
Viewing data Volumes
docker volume ls
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Creating a Data Volume
docker volume create nginx_vol
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View data volume details
docker volume inspect nginx_vol
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Create containers with data volumes
docker run -d --name=nginx03 -p 88:80 --mount src=nginx_vol,dst=/usr/share/nginx/html/ nginx
Copy the codeError: Using –mount
unknown flag: –mount
Solution: Use -v or use version 17.06 or later
docker run -d --name=nginx03 -p 88:80 -v nginx_vol:/usr/share/nginx/html/ nginx
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Take a look at the directory where the container nginx03 is hosted
ls /var/lib/docker/volumes/nginx_vol/_data
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Modify the/var/lib/docker/volumes/nginx_vol / _data while forming the index in the directory. The HTML file
Prove the/var/lib/docker/volumes/nginx_vol / _data while forming files in the directory and nginx03 container is Shared
Docker inspect nginx03Copy the code
Pause the nginx03 container and create the nginx04 container
Found that the data was still not lost
Some students will ask, if these two containers are deleted, will the files of the data volume still exist?
The answer is yes, because the data volume is independent of the container
Note: If the data volume is deleted, the data file does not exist
summary
Volume features:
- Data is shared between multiple running containers
- When the container is stopped or removed, the data volume still exists
- Multiple containers can mount the same volume simultaneously
- Data in the volume is deleted only when the volume is deleted
- Store the container’s data on a remote host or other storage
- /var/lib/docker/volumes/