3.6 KiB
| title | description | keywords |
|---|---|---|
| inspect | The inspect command description and usage | inspect, container, json |
inspect
Usage: docker inspect [OPTIONS] NAME|ID [NAME|ID...]
Return low-level information on Docker object(s) (e.g. container, image, volume,
network, node, service, or task) identified by name or ID
Options:
-f, --format Format the output using the given Go template
--help Print usage
-s, --size Display total file sizes if the type is container
--type Return JSON for specified type
Description
Docker inspect provides detailed information on constructs controlled by Docker.
By default, docker inspect will render results in a JSON array.
Request a custom response format (--format)
If a format is specified, the given template will be executed for each result.
Go's text/template package describes all the details of the format.
Specify target type (--type)
--type container|image|node|network|secret|service|volume|task|plugin
The docker inspect command matches any type of object by either ID or name.
In some cases multiple type of objects (for example, a container and a volume)
exist with the same name, making the result ambigious.
To restrict docker inspect to a specific type of object, use the --type
option.
The following example inspects a volume named "myvolume"
$ docker inspect --type=volume myvolume
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