DOCKER COMMANDS

A list of my commonly used Docker commands.

curl -fsSL https://get.docker.com -o get-docker.sh
sudo sh get-docker.sh

When you install Docker on a linux host you're actually installing three different competence.
DOCKER ENGINE

1. DOCKER CLI
2. REST API
3. DOCKER DEAMON

• The DOCKER CLI is nothing but the command line interface to perform actions such as running a container stopping containers destroying images etc. It uses the REST API to interact with the DOCKER DEAMON.

• The DOCKER REST API server is the API interface that programs can use to talk to the DEAMON and provide instructions.

• The DOCKER DEAMON is a background process that manages Docker objects such as the images containers volumes and networks.

docker -H={{remote-docker-engine}}:{{port}} run {{image}}

docker version

sudo apt install net-tools
sudo apt install jq

sudo vi ~/.bashrc

Paste The Below Code At The Bottom Of The bashrc File

dps()  {
  docker ps $@ --format "table{{ .ID}}\\t{{ .Image }}\\t{{ .Names }}\\t{{ .Status }}\\t{{ .Command }}\\t{{ .Status }}\\t{{ .Ports }}" | awk '
  NR % 2 == 0 {
    printf "\033[0;32m";
  }
  NR % 2 == 1 {
    printf "\033[0;34m";
  }
  NR == 1 {
    printf "\033[1;31m";
    PORTSPOS = index($0, "PORTS");
    PORTS = "PORTS";
    PORTSPADDING = "\n";
    for(n = 1; n < PORTSPOS; n++)
    PORTSPADDING = PORTSPADDING " ";
  }
  NR > 1 {
    PORTS = substr($0, PORTSPOS);
    gsub(/, /, PORTSPADDING, PORTS);
  }
  {
    printf "%s%s\n\n", substr($0, 0, PORTSPOS - 1), PORTS;
  }
  END {
    printf "\033[0m";
  }
  '
}
dpsa() { dps -a $@; }


dpsjson()  {
  docker ps --format "{{json .}}" --no-trunc | jq
}

source ~/.bashrc
dps
dpsjson

Run an instance of the image on the docker host, if image is not on the host it will go to docker hub and pull

when you run the docker run Ubuntu command, it runs an instance of ubuntu image and exits immediately. If you list all containers using docker ps -a including those that are stopped you will see that the new container you ran is in an exited stage. Because containers are not meant to host an operating system. Containers are meant to run a specific task or process, Once the task is complete the container exits a container only lives as long as the process inside it is alive. If the web service inside the container is stopped or a crash then the container exits. This is why when you run a container from an ubuntu image it stops immediately because Ubuntu is just an image of an operating system that is used as the base image for other applications. There is no process or application running in it by default.

docker run nginx is same as docker run docker.io/nginx/nginx

image: docker.io/nginx/nginx

where
docker.io is the REGISTRY (Default)
nginx is the USER ACCOUNT (if not given use the same name as the IMAGE REPOSITORY)
nginx is the IMAGE REPOSITORY

DOCKER REGISTRY (docker.io, google's registry gcr.io, aws, azure, dcp)

docker pull `image`

docker ps
docker ps -a
docker ps | less -S
docker ps --format 'table {{ .ID }}\t{{.Image}}\t{{ .Names }}\t{{ .Ports }}' -s
docker ps --format 'table {{ .ID }}\t{{.Image}}\t{{ .Names }}\t{{ .Ports }}' | less -S
docker ps --format "{{json .}}" --no-trunc
docker ps --format "{{json .}}" --no-trunc | jq

docker stop `conatiner`

docker images

docker rm `container` `container` `container`

Must ensure no conatiner running off of that image, must stop and delete all container first

docker rmi `image`

docker exec -it CONTAINER_ID /bin/bash
docker exec -it CONTAINER_ID bash
docker exec -it CONTAINER_ID sh

docker exec -it `container` ps -eaf

Default IP of a docker container is 172.X.0.X, this is internal IP and only accessible within docker host. Default IP of the docker host is 192.168.1.X / host.docker.internal, this IP is accessible outside the docker host.

MAP port to docker container

-p 80:5000

docker run -v /opt/datadir:/var/lib/mysql mysql

By running this command we are going to save mysql data in our local storage so that even if the container is remove we have the data.

docker inspect `container`

docker inspect -f '{{range.NetworkSettings.Networks}}{{.IPAddress}}{{end}}' `container_id`
docker inspect `container_id` | grep IPAddress
docker inspect `container_id` | jq .[0].NetworkSettings.Networks[].IPAddress

docker logs `container`

docker history `container`