Docker - start new docker container using existing image

In this short article, we would like to show how to start a new Docker container using an existing image.

Quick solution:

docker run -d -i -t MY_IMAGE_ID /bin/bash

# or

docker run -d -i -t --name MY_NEW_CONTAIER_NAME MY_IMAGE_ID /bin/bash

Practical example

The following command creates a container for indicated image (4ea2949e4cb8):

docker run -d -i -t 4ea2949e4cb8 /bin/bash

# or with port redirection and image/repository name

docker run -d -i -t --name postgres-shop -p 5432:5432 postgres /bin/bash

Where:

• -d means the terminal is detached (we will not see in command line docker container output),
• -i means keeping opened STDIN even terminal is detached,
• -t means the container will use pseudo-tty,
• --name postgres-shop means the container will be named as postgres-shop,
• -p 5432:5432 means 5432 container port will be redirected to localhost:5432 port,
• 4ea2949e4cb8 is IMAGE ID that should be changed to the current one,
• /bin/bash used tty.

You can run docker images command to see all available images:

$ docker images
REPOSITORY         TAG          IMAGE ID            CREATED             SIZE
postgres           latest       4ea2949e4cb8        10 days ago         314MB

You can run docker ps command to see all started containers (started from images):

$ docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS               NAMES
e4a5a3b62cd4        4ea2949e4cb8        "docker-entrypoint.s…"   1 second ago        Up 1 second         5432/tcp            reverent_panini

Running docker image with attached terminal

Below command runs image as Docker container opening terminal in the same command line.

docker run -i -t 4ea2949e4cb8 /bin/bash