Docker Cookbook

9.1 Getting Detailed Information About a Container with
docker inspect
Problem
You want to get detailed information about a container—such as when it was created,
what command was passed to the container, what port mappings exist, what IP
address the container has, and so forth.
Solution
Use the 
docker inspect
command. For example, start an Nginx container and use
inspect
:
$ docker run -d -p 80:80 nginx
$ docker inspect kickass_babbage
[{
"AppArmorProfile": "",
"Args": [
"-g",
274 | Chapter 9: Monitoring Containers

---

"daemon off;"
],
...
"ExposedPorts": {
"443/tcp": {},
"80/tcp": {}
},
...
"NetworkSettings": {
...
"IPAddress": "172.17.0.3",
...
The 
inspect
command also works on an image:
$ docker inspect nginx
[{
"Architecture": "amd64",
"Author": "NGINX Docker Maintainers \"[e-mail]\"",
"Comment": "",
"Config": {
"AttachStderr": false,
"AttachStdin": false,
"AttachStdout": false,
"Cmd": [
"nginx",
"-g",
"daemon off;"
],
...
Discussion
The Docker 
inspect
command takes a 
format
option. You can use it to specify a
Golang template and extract specific information about a container or image instead
of getting the full JSON output:
$ docker inspect --help
Usage: docker inspect [OPTIONS] CONTAINER|IMAGE [CONTAINER|IMAGE...]
Return low-level information on a container or image
-f, --format="" Format the output using the given go template.
--help=false Print usage
For example, to get the IP address of a running container and check its state:
$ docker inspect -f '{{ .NetworkSettings.IPAddress }}' kickass_babbage
172.17.0.3
$ docker inspect -f '{{ .State.Running }}' kickass_babbage
true