docker inspect

Estimated reading time: 2 minutes

Edge only: This is the CLI reference for Docker CE Edge versions. Some of these options may not be available to Docker CE stable or Docker EE. You can view the stable version of this CLI reference or learn about Docker CE Edge.

Description

Return low-level information on Docker objects

Usage

docker inspect [OPTIONS] NAME|ID [NAME|ID...]

Options

Name, shorthand Default Description
--format, -f   Format the output using the given Go template
--size, -s false Display total file sizes if the type is container
--type   Return JSON for specified type

Parent command

Command Description
docker The base command for the Docker CLI.

Extended description

ker inspect provides detailed information on constructs controlled by Docker.

By default, docker inspect will render results in a JSON array.

Examples

Get an instance’s IP address

For the most part, you can pick out any field from the JSON in a fairly straightforward manner.

$ docker inspect --format='{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' $INSTANCE_ID

Get an instance’s MAC address

$ docker inspect --format='{{range .NetworkSettings.Networks}}{{.MacAddress}}{{end}}' $INSTANCE_ID

Get an instance’s log path

$ docker inspect --format='{{.LogPath}}' $INSTANCE_ID

Get an instance’s image name

$ docker inspect --format='{{.Config.Image}}' $INSTANCE_ID

List all port bindings

You can loop over arrays and maps in the results to produce simple text output:

$ docker inspect --format='{{range $p, $conf := .NetworkSettings.Ports}} {{$p}} -> {{(index $conf 0).HostPort}} {{end}}' $INSTANCE_ID

Find a specific port mapping

The .Field syntax doesn’t work when the field name begins with a number, but the template language’s index function does. The .NetworkSettings.Ports section contains a map of the internal port mappings to a list of external address/port objects. To grab just the numeric public port, you use index to find the specific port map, and then index 0 contains the first object inside of that. Then we ask for the HostPort field to get the public address.

$ docker inspect --format='{{(index (index .NetworkSettings.Ports "8787/tcp") 0).HostPort}}' $INSTANCE_ID

Get a subsection in JSON format

If you request a field which is itself a structure containing other fields, by default you get a Go-style dump of the inner values. Docker adds a template function, json, which can be applied to get results in JSON format.

$ docker inspect --format='{{json .Config}}' $INSTANCE_ID