The List of Popular Docker Commands

Posted in

The List of Popular Docker Commands
paritoshlouhan

Paritosh Louhan
Last updated on May 22, 2024

    Docker has become an important aspect of the deployment of software applications. It helps in reducing complexities that occur in the different phases of software development , from development to deployment, in the case of different environments, and brings portability to the picture. This eventually means that developers can now focus more on the development part rather than worrying about whether their software is going to work in production or not due to issues related to dependencies and environment configuration differences.

    Earlier, I have covered how you can set up docker on Windows 11? and some basic terminologies that you should know before starting with this tutorial.

    You can refer to my previous blog here.

    In this blog post, we will learn some basic Docker commands with their examples. We will be using Windows Powershell to run our Docker commands on Windows.

    To start with, any command I can run on the terminal. I always prefer to first look at the help section.

    docker help

    You can use the help option to see the various options and commands that one can use with Docker.

    Syntax:

    docker --help

    Output:

    Usage: docker [OPTIONS] COMMAND

    A self-sufficient runtime for containers

    Options:

    --config string

    Location of client config files

    (default "C:\\Users\\avyuk\\.docker")

    -c, --context string

    Name of the context to use to connect to the daemon (overrides DOCKER_HOST env var and default context set with "docker context use")

    -D, --debug

    Enable debug mode

    -H, --host list

    Daemon socket(s) to connect to

    -l, --log-level string

    Set the logging level

    ("debug"|"info"|"warn"|"error"|"fatal")

    (default "info")

    --tls

    Use TLS; implied by --tlsverify

    --tlscacert string

    Trust certs signed only by this CA (default

    "C:\\Users\\avyuk\\.docker\\ca.pem")

    --tlscert string

    Path to TLS certificate file (default "C:\\Users\\avyuk\\.docker\\cert.pem")

    --tlskey string

    Path to TLS key file (default "C:\\Users\\avyuk\\.docker\\key.pem")

    --tlsverify

    Use TLS and verify the remote

    -v, --version

    Print version information and quit

    Management Commands:

    builder

    Manage builds

    buildx*

    Docker Buildx (Docker Inc., v0.9.1)

    compose*

    Docker Compose (Docker Inc., v2.10.2)

    config

    Manage Docker configs

    container

    Manage containers

    context

    Manage contexts

    extension*

    Manages Docker extensions (Docker Inc., v0.2.9)

    image

    Manage images

    manifest

    Manage Docker image manifests and manifest lists

    network

    Manage networks

    node

    Manage Swarm nodes

    plugin

    Manage plugins

    sbom*

    View the packaged-based Software Bill Of Materials (SBOM) for an image (Anchore Inc., 0.6.0)

    scan*

    Docker Scan (Docker Inc., v0.19.0)

    secret

    Manage Docker secrets

    service

    Manage services

    stack

    Manage Docker stacks

    swarm

    Manage Swarm

    system

    Manage Docker

    trust

    Manage trust on Docker images

    volume

    Manage volumes

    Commands:

    attach

    Attach local standard input, output, and error streams to a running container

    build

    Build an image from a Dockerfile

    commit

    Create a new image from a container's changes

    cp

    Copy files/folders between a container and the local filesystem

    create

    Create a new container

    diff

    Inspect changes to files or directories on a container's filesystem

    events

    Get real time events from the server

    exec

    Run a command in a running container

    export

    Export a container's filesystem as a tar archive

    history

    Show the history of an image

    images

    List images

    import

    Import the contents from a tarball to create a filesystem image

    info

    Display system-wide information

    inspect

    Return low-level information on Docker objects

    kill

    Kill one or more running containers

    load

    Load an image from a tar archive or STDIN

    login

    Log in to a Docker registry

    logout

    Log out from a Docker registry

    logs

    Fetch the logs of a container

    pause

    Pause all processes within one or more containers

    port

    List port mappings or a specific mapping for the container

    ps

    List containers

    pull

    Pull an image or a repository from a registry

    push

    Push an image or a repository to a registry

    rename

    Rename a container

    restart

    Restart one or more containers

    rm

    Remove one or more containers

    rmi

    Remove one or more images

    run

    Run a command in a new container

    save

    Save one or more images to a tar archive (streamed to STDOUT by default)

    search

    Search the Docker Hub for images

    start

    Start one or more stopped containers

    stats

    Display a live stream of container(s) resource usage statistics

    stop

    Stop one or more running containers

    tag

    Create a tag TARGET_IMAGE that refers to SOURCE_IMAGE

    top

    Display the running processes of a container

    unpause

    Unpause all processes within one or more containers

    update

    Update configuration of one or more containers

    version

    Show the Docker version information

    wait

    Block until one or more containers stop, then print their exit codes

    docker COMMAND --help

    You can also find options for each command by looking into the help section of individual command using above syntax.

    Example:

    docker search --help

    docker search --help

    The List of Popular Docker Commands

    Let us now begin with the discussion of the most-used and popular Docker commands that you must know while working with Docker.

    1. docker search

    The docker search command is going to search the docker hub for images.

    Syntax:

    docker search <imagename>

    Command:

    docker search java

    Output:

    docker search java --no-trunc

    The -- no-trunc flag is used to see the complete description in the above command. If not used, the description will be truncated. The above command searched and found all the Java distributions that are available in the Docker Hub registry.

    Also, note that we have seen only 25 records since it is the default limit. To increase the limit, you can run the below command:

    docker search java --no-trunc --limit 30

    Output:

     docker search <imagename>

    2. Docker version

    Use this command to check the version of Docker installed on your system.

    Syntax:

    docker --version

    Example:

    Docker Version

    3. Docker pull command

    The Docker pull command can be used to pull the available Docker images from the Docker Hub registry.

    Syntax:

    docker --pull

    Docker pull works in two ways:

    • docker pull <imagename>

    The above command will pull the image with the given name with the latest tag.

    Example:

    Docker Pull

    • docker pull <imagename>:<tagname>

    Example:

    Docker Pull

    The above syntax will help to pull the specific version of that image as specified using tagname.

    Note: To search for available tags, you can search the web. You will find the information on the Docker Hub pages as follows:

    Docker Hub pages

    4. docker images

    This command helps to list all the Docker Images available on your local system.

    Syntax:

    docker images

    As per the tutorial flow, we have pulled two images of OpenJDK. So, we should be able to see only two images, one with the latest tag and another with the 20-oraclelinux8 tag.

    docker images

    5. docker rmi

    You can use this command to delete Docker Images from local. You can remove one or many images by passing the names of the images.

    Syntax:

    docker rmi [OPTIONS] IMAGE [IMAGE...]

    Example:
    docker rmi

    In the above example, I have removed two images where the image names are space separated.

    You can also remove Docker Images from the Docker desktop using the “Clean up” button in the Images tab as per the below screenshot:
    Clean Up

    6. docker run

    This command is used to run an image in a container.

    Syntax:

    docker run [OPTIONS] IMAGE [COMMAND] [ARG...]

    Example:

    PS C:\Users\avyuk> docker run -it ubuntu

    Output:

    Unable to find image 'ubuntu:latest' locally
    latest: Pulling from library/ubuntu
    2b55860d4c66: Pull complete
    Digest: sha256:20fa2d7bb4de7723f542be5923b06c4d704370f0390e4ae9e1c833c8785644c1
    Status: Downloaded newer image for ubuntu:latest
    root@dd984bb81945:/#

    In the above example, we need to notice a few points:


    1) If we are running an image that does not exist locally, it tries to fetch it from the Docker Hub registry and execute it if it is able to find it there.

    2) We have interactively executed the command (using -it flag), which means after the image is run in a container, we will enter into the container. This can be seen since the last line is pointing to the root user while we were working from “PS C:\Users\avyuk”

    You can play around inside the container now until the container is alive.

    Example:

    root@dd984bb81945:/# ls
    bin boot dev etc home lib lib32 lib64 libx32 media mnt opt proc root run sbin srv sys tmp usr var
    root@dd984bb81945:/# touch fileInContainer.txt
    root@dd984bb81945:/# echo "Hey I have created a file in the container. This file is alive until the container is alive." > fileInContainer.txt root@dd984bb81945:/# cat fileInContainer.txt
    Hey I have created a file in the container. This file is alive until the container is alive.

    We will now try to learn some other docker commands that will continue to the above example, which we have used to create a container using docker run.

    You can provide meaningful names to your container using the --name flag below. If the name is not provided, the daemon generates a random name for you.

    docker run

    Output:

    Docker PS

    The following are the other options that you can use with the docker run command:

    Options:

    --add-host list

    Add a custom host-to-IP mapping (host:ip)

    -a, --attach list

    Attach to STDIN, STDOUT or STDERR

    --blkio-weight uint16

    Block IO (relative weight), between 10 and 1000, or 0 to disable (default 0)

    --blkio-weight-device list

    Block IO weight (relative device weight) (default [])

    --cap-add list

    Add Linux capabilities

    --cap-drop list

    Drop Linux capabilities

    --cgroup-parent string

    Optional parent cgroup for the container

    --cgroupns string

    Cgroup namespace to use (host|private)

    • 'host': Run the container in the Docker host's cgroup namespace
    • 'private': Run the container in its own private cgroup namespace
    • ' ': Use the cgroup namespace as configured by the

    Default-cgroupns-mode option on the daemon (default)

    --cidfile string

    Write the container ID to the file

    --cpu-period int

    Limit CPU CFS (Completely Fair Scheduler) period

    --cpu-quota int

    Limit CPU CFS (Completely Fair Scheduler) quota

    --cpu-rt-period int

    Limit CPU real-time period in microseconds

    --cpu-rt-runtime int

    Limit CPU real-time runtime in microseconds

    -c, --cpu-shares int

    CPU shares (relative weight)

    --cpus decimal

    Number of CPUs

    --cpuset-cpus string

    CPUs in which to allow execution (0-3, 0,1)

    --cpuset-mems string

    MEMs in which to allow execution (0-3, 0,1)

    -d, --detach

    Run container in background and print container ID

    --detach-keys string

    Override the key sequence for detaching a container

    --device list

    Add a host device to the container

    --device-cgroup-rule list

    Add a rule to the cgroup allowed devices list

    --device-read-bps list

    Limit read rate (bytes per second) from a device (default [])

    --device-read-iops list

    Limit read rate (IO per second) from a device (default [])

    --device-write-bps list

    Limit write rate (bytes per second) to a device (default [])

    --device-write-iops list

    Limit write rate (IO per second) to a device (default [])

    --disable-content-trust

    Skip image verification (default true)

    --dns list

    Set custom DNS servers

    --dns-option list

    Set DNS options

    --dns-search list

    Set custom DNS search domains

    --domainname string

    Container NIS domain name

    --entrypoint string

    Overwrite the default ENTRYPOINT of the image

    -e, --env list

    Set environment variables

    --env-file list

    Read in a file of environment variables

    --expose list

    Expose a port or a range of ports

    --gpus gpu-request

    GPU devices to add to the container ('all' to pass all GPUs)

    --group-add list

    Add additional groups to join

    --health-cmd string

    Command to run to check health

    --health-interval duration

    Time between running the check (ms|s|m|h) (default 0s)

    --health-retries int

    Consecutive failures needed to report unhealthy

    --health-start-period duration

    Start period for the container to initialize before starting health-retries countdown (ms|s|m|h) (default 0s)

    --health-timeout duration

    Maximum time to allow one check to run (ms|s|m|h) (default 0s)

    --help

    Print usage

    -h, --hostname string

    Container host name

    --init

    Run an init inside the container that forwards signals and reaps processes

    -i, --interactive

    Keep STDIN open even if not attached

    --ip string

    IPv4 address (e.g., 172.30.100.104)

    --ip6 string

    IPv6 address (e.g., 2001:db8::33)

    --ipc string

    IPC mode to use

    --isolation string

    Container isolation technology

    --kernel-memory bytes

    Kernel memory limit

    -l, --label list

    Set meta data on a container

    --label-file list

    Read in a line delimited file of labels

    --link list

    Add link to another container

    --link-local-ip list

    Container IPv4/IPv6 link-local addresses

    --log-driver string

    Logging driver for the container

    --log-opt list

    Log driver options

    --mac-address string

    Container MAC address (e.g., 92:d0:c6:0a:29:33)

    -m, --memory bytes

    Memory limit

    --memory-reservation bytes

    Memory soft limit

    --memory-swap bytes

    Swap limit equal to memory plus swap: '-1' to enable unlimited swap

    --memory-swappiness int

    Tune container memory swappiness (0 to 100) (default -1)

    --mount mount

    Attach a filesystem mount to the container

    --name string

    Assign a name to the container

    --network network

    Connect a container to a network

    --network-alias list

    Add network-scoped alias for the container

    --no-healthcheck

    Disable any container-specified HEALTHCHECK

    --oom-kill-disable

    Disable OOM Killer

    --oom-score-adj int

    Tune host's OOM preferences (-1000 to 1000)

    --pid string

    PID namespace to use

    --pids-limit int

    Tune container pids limit (set -1 for unlimited)

    --platform string

    Set platform if server is multi-platform capable

    --privileged

    Give extended privileges to this container

    -p, --publish list

    Publish a container's port(s) to the host

    -P, --publish-all

    Publish all exposed ports to random ports

    --pull string

    Pull image before running ("always"|"missing"|"never") (default "missing")

    --read-only

    Mount the container's root filesystem as read only

    --restart string

    Restart policy to apply when a container exits (default "no")

    --rm

    Automatically remove the container when it exits

    --runtime string

    Runtime to use for this container

    --security-opt list

    Security Options

    --shm-size bytes

    Size of /dev/shm

    --sig-proxy

    Proxy received signals to the process (default true)

    --stop-signal string

    Signal to stop a container (default "15")

    --stop-timeout int

    Timeout (in seconds) to stop a container

    --storage-opt list

    Storage driver options for the container

    --sysctl map

    Sysctl options (default map[])

    --tmpfs list

    Mount a tmpfs directory

    -t, --tty

    Allocate a pseudo-TTY

    --ulimit ulimit

    Ulimit options (default [])

    -u, --user string

    Username or UID (format:<name|uid>[:<group|gid>])

    --userns string

    User namespace to use

    --uts string

    UTS namespace to use

    -v, --volume list

    Bind mount a volume

    --volume-driver string

    Optional volume driver for the container

    --volumes-from list

    Mount volumes from the specified container(s)

    -w, --workdir string

    Working directory inside the container

    7. docker ps

    This command lists all the running containers.

    Syntax:

    docker ps [OPTIONS]

    Example:

    Docker PS

    Please note that you will be running Docker commands in your system and not in the container.

    Here are some important options that you can use with the docker ps command:

    docker ps command

    Note: docker ps -a will show all containers while the default command will just show the running containers.

    The other options that you can use with docker ps are as follows:

    -a, --all

    Show all containers (default shows just running)

    -f, --filter filter

    Filter output based on conditions provided

    --format string

    Pretty-print containers using a Go template

    -n, --last int

    Show n last created containers (includes all states) (default -1)

    -l, --latest

    Show the latest created container (includes all states)

    --no-trunc

    Don't truncate output

    -q, --quiet

    Only display container IDs

    -s, --size

    Display total file sizes

    8. docker stop

    Use this command to stop a running container. Docker stop will either need the container name or container id as an argument. With this command, you can stop one or many containers:

    Syntax:

    docker stop [OPTIONS] CONTAINER [CONTAINER...]

    Example:

    Docker Stop

    This will exit the container on another terminal as follows:

    another terminal

    Once the container has exited, you will only be able to list the container using docker ps -a since the status of the container has been changed from running to the exit.

    docker ps -a

    9. docker restart

    The docker restart command restarts a stopped container. Below is an example of how you can use this command. With this command, you can restart one or many containers.

    Syntax:

    docker restart [OPTIONS] CONTAINER [CONTAINER...]

    Example:

    docker restart

    Conclusion

    In this blog, we have covered the basic commands to kick-start with docker. Stay tuned with us for more docker-related blogs. We will be covering how to create your custom docker image in the next blog series using docker build and docker tag commands.

    Thanks for reading. Happy learning :)

    People are also reading:

    FAQs


    The Docker engine is responsible for storing images and running containers. To do that operation, the docker engine reserves some amount of storage space termed as a 'storage pool'. After completely utilizing this storage space, the docker engine will start failing. Since docker images take most of the storage space, it's always a good idea to remove unwanted images. Because they can be redownloaded if required. But you need to be careful about the images which are created by you and are not stored elsewhere other than local storage.

    Docker Images and other objects are stored inside the docker directory in the local machine. By default, the location of the docker directory is '/var/lib/docker' for Linux systems. While for windows 11, you can find at “\\wsl.localhost\docker-desktop-data\data\docker\image” location. You can just add this location in the address bar in file explorer.

    No, a container should be in a stopped state before it can be removed.

    Leave a Comment on this Post

    0 Comments