How Can I Increase Docker Drive Space Size

How to Check Disk Infinite Usage for Docker Images & Containers

Sep 21, 2021, 8:00 am EDT | 2 min read

With containerized applications running in isolated environments, it tin exist harder than usual to track down problems with applications using too much storage space. Fortunately, Docker provides commands for managing container disk usage.

Doing a Quick Check

And if y'all desire to check how much space Docker is using, you tin use the built in commanddocker system df, likewise as the Linux command du to get the size of the unabridged directory.

docker system df sudo du -sh /var/lib/docker/

This control shows static images, containers that have made changes to their filesystem (eastward.g., log files), and volumes bound to the containers.

However, this isn't entirely accurate—here, I have many containers running, simply they're all storing information in bind mounts on the host OS, not volumes.

Cleaning Docker Images

Docker Images are different than running containers; they're the files that you download from the Docker Hub to launch a container from. They're ordinarily pretty big, containing all the necessary code to run a basic Os and your application.

Each version of an prototype is split up, but information technology's stored in layers, so multiple new versions won't take upward twice every bit much storage infinite. You can view all images with image ls:

docker image ls

Cleaning these is easy; you don't desire to remove images of running containers, of course, but removing old images is fine—they'll simply be re-downloaded when needed.

You can clip all images, or manually delete ane past ID:

docker epitome prune -a docker prototype rm 3a8d8f76e7f8f

Checking Running Container Usage

Containers are a bit trickier to track down, since they can use data in many different ways:

Underlying image: each container volition need to store its image, just this is reused across containers.
Modification layer: if a container writes to its filesystem, such every bit log files, it will be saved in a new layer on pinnacle of the underlying epitome. This is unique to each container.
Volumes: containers can have virtual drives mounted to them, which store data directly on disk exterior the Docker storage organization.
Demark Mounts: containers can optionally access directories on the host direct.

Everything except bind mounts will show upwards in docker organization df output. If y'all want to view stats for each container, Docker provides a flag for the ps command to list the usage:

docker ps --size

Here, this shows the size on deejay, as well as the virtual size (which includes the shared underlying image). Since these containers aren't using any storage outside their demark mounts, the size is zero bytes.

Debugging Mounts (Binds and Volumes)

To view mount usage, for both direct bind mounts and managed volumes, y'all'll have to get the size of them from the host OS. If y'all don't know where they are, you tin can run docker container ls to become a container'due south ID, and so run docker inspect to catch the mount info:

docker inspect a1c904020044 -f '{{json .Mounts}}'            [{"Blazon":"bind","Source":"/home/daemon-data/921ff235-5075-4d64-b977-8d02cc3dacc9","Destination":"/home/container","Style":"","RW":true,"Propagation":"rprivate"}]

And then, yous can check the total size with du -sh:

sudo du -sh /path/to/mount/

Pruning Containers And Volumes

Docker never removes containers or volumes (unless you run containers with the --rm flag), equally doing so could lose your data. Nonetheless, you lot may have old information backed up that needs to be garbage collected.

Much similar images, Docker provides a prune command for containers and volumes:

docker container prune  docker volume prune

Manually Debugging

If you take direct admission to the server running Docker, you lot tin can pop open a shell in the container:

sudo docker exec -it containerID /bin/bash

and run du -sh on the entire matter, which volition return all information, including the paradigm size, data on bind mounts, and data in volumes.

sudo du -sh /