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kobevino

Bind mount vs Named volume

Tue, Sep 30, 2025

I'll dive into the difference between bind mounts and named volumes and show you how to use volumes for persistent storage.

Bind mount

bind-mount

# Pull docker image
$ docker pull httpd:2.4
# Run container
$ docker run -d -p 8080:80 --name apache -v /var/data:/usr/local/apache2/htdocs/ httpd:2.4
# Create index.html
$ echo "<h1>Hello World</h1>" | sudo tee /var/data/index.html
# Attach to the container's shell
$ docker exec -it apache /bin/bash
# Check disk capacity on apache container shell
$ df -h htdocs
Filesystem                         Size  Used Avail Use% Mounted on
/dev/mapper/ubuntu--vg-ubuntu--lv  9.8G  6.5G  2.8G  71% /usr/local/apache2/htdocs

Bind mount is when a host directory(/var/data) is mounted into a container(/usr/local/apache2/htdocs/).

# Pull docker image
$ docker pull nginx
# Run container
$ docker run -d -p 8081:80 --name nginx -v /var/data:/usr/share/nginx/html/ nginx
# Attach to the container's shell
$ docker exec -it nginx /bin/bash
# Check disk capacity on apache container shell
$ df -h htdocs
Filesystem                         Size  Used Avail Use% Mounted on
/dev/mapper/ubuntu--vg-ubuntu--lv  9.8G  6.7G  2.6G  73% /usr/share/nginx/html

When we remove the container and create a new one, the mounted host directory (/var/data) can be reused as long as the directory is not deleted.

Named Volume

named-volume

# Create a volume
$ docker volume create sample
# Show a list of volume
$ dockver volume ls
DRIVER    VOLUME NAME
local     sample
# Show information of sample volume
$ docker volume inspect sample
[
    {
        "CreatedAt": "2025-09-30T10:44:47Z",
        "Driver": "local",
        "Labels": null,
        "Mountpoint": "/var/lib/docker/volumes/sample/_data",
        "Name": "sample",
        "Options": null,
        "Scope": "local"
    }
]
# Create a container
$ docker run -d -p 8080:80 --name apache -v sample:/usr/local/apache2/htdocs/ httpd:2.4
# Check a mountpoint
$ sudo ls /var/lib/docker/volumes/sample/_data
index.html

Unlike bind mounts, named volumes are Docker-managed storage that can be attached to containers without directly linking to a host directory.

Wrap up

  • Bind Mount : host directory -------> container directory
  • Named Volume : Docker-managed volume <------> container directory

By understanding these options, you can ensure that your data remains safe even when containers are recreated.