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JSON on Docker

What is JSON? JSON is short for J ava S cript O bject N otation. It implements a lightweight data interchange format based on a subset of JavaScript language. JSON provides a way to store information such that it is easy for machines to parse and generate. Docker uses JSON as its default Logging Driver to communicate information. JSON is a way to store information in an organized, easy-to-access manner. It is used primarily to transmit data, as an alternative to XML . As an example of how Docker leverages JSON, here's an excerpt of the docker inspect <Name | ID> output: $ docker inspect 978d [     {         "Id": "sha256:978d85d02b87aea199e4ae8664f6abf32fdea331884818e46b8a01106b114cee",         "RepoTags": [             "debian:latest"         ],         "Container": "4799c1aee3356a0d8e51a1e6e48edc1c4ca224e55750e26916f917bdecd96079",         &quo
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Docker Command Flowchart

Docker Command Flowchart Inspired by a post at www.troubleshooters.com this flowchart illustrates some of the Docker objects and the commands that apply to them. For example, to preserve changes made in a container object and convert it into an image , use the docker commit command. References: http://www.troubleshooters.com/linux/docker/docker_newbie.htm Licensed under a Creative Commons Attribution 4.0 International License .

Docker Commands: docker network

Docker Commands: docker network docker network connect Connect a running container to a network. Use docker inspect 00db80208c35 to confirm the network connection. In this case, the container is connected to two networks: Licensed under a Creative Commons Attribution 4.0 International License .

Docker Commands: docker inspect

Docker Commands: docker inspect docker inspect Return low-level information on Docker objects The target of this command is an object that can be identified via a Name or an ID , e.g. image , container , network , service , etc. The output of the command is information about the object displayed as a JSON array. @ubuntu:~ $ docker inspect wizardly_jang [ { "Id": "c794e33bda6bfa60cdc039795ad7712c62df68ca5f8a6d14b906a6a06bc08e43", "Created": "2017-04-01T06:02:04.840341671Z", "Path": "nginx", "Args": [ "-g", "daemon off;" ], "State": { "Status": "running", "Running": true, "Paused": false, "Restarting": false, "OOMKilled": false, "Dead"

Docker Commands: docker history

Docker Commands: docker history docker history <image_name> Show the history of an image. In effect, it identifies the "layers" in an image. Note: There is an online tool, imagelayers.io that can be used to visualize the layers of an image. Licensed under a Creative Commons Attribution 4.0 International License .

Docker Commands: docker diff

Docker Commands: docker diff docker diff <container ID> Inspect the changes made to a container's filesystem. Note: A Added File C Changed File D Deleted File Licensed under a Creative Commons Attribution 4.0 International License .

Docker Commands: docker exec

Docker Commands: docker exec docker exec Run a new process in an already running container Use docker exec to run a secondary process inside a container. Let's say the Nginx web proxy container is running in detached ( -d ) mode, you can use docker exec to start another process in that container. In the example below, the process status command, ps  is run inside the Nginx container. Note: If the container is stopped, it must first be started with docker start . Licensed under a Creative Commons Attribution 4.0 International License .