docker inspect

Description

Return low-level information on Docker objects

Usage

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

Extended description

Docker inspect provides detailed information on constructs controlled by Docker.

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

For example uses of this command, refer to the examples section below.

Options

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

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

Parent command

Command Description
docker The base command for the Docker CLI.