How to use Docker on my servelets?

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How to use Docker on my servelets?

Firstly, you would need to spin off a servelet with below OS template:

Ubuntu 18.04.1 (64-bit) + Docker 18.06.1 CE

The OS template is running Ubuntu 18.04.1 LTS (64-bit) with Docker already pre-installed. When the servelet is provisioned, the Docker daemon should already have been running. You may verify by running below command to confirm:

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ps awx | grep docker
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For example:

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root@ubuntu1804-64b:~# ps awx | grep docker
816 ?        Ssl    0:01 /usr/bin/dockerd -H fd://
885 ?        Ssl    0:00 docker-containerd --config /var/run/docker/containerd/containerd.toml
1496 pts/0    S+     0:00 grep --color=auto docker
===

You can see that the Docker daemon process is already running on pid 816 (this number may vary). If for some reason, the Docker daemon is not running, you can start the daemon by running below command:

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docker -d &
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To start using Docker and list down the available commands, type:

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docker
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For example:

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root@ubuntu1804-64b:~# docker

Usage: docker [OPTIONS] COMMAND

A self-sufficient runtime for containers

Options:
      --config string      Location of client config files (default "/root/.docker")
-D, --debug              Enable debug mode
-H, --host list          Daemon socket(s) to connect to
-l, --log-level string   Set the logging level ("debug"|"info"|"warn"|"error"|"fatal") (default "info")
      --tls                Use TLS; implied by --tlsverify
      --tlscacert string   Trust certs signed only by this CA (default "/root/.docker/ca.pem")
      --tlscert string     Path to TLS certificate file (default "/root/.docker/cert.pem")
      --tlskey string      Path to TLS key file (default "/root/.docker/key.pem")
      --tlsverify          Use TLS and verify the remote
-v, --version            Print version information and quit

Management Commands:
config      Manage Docker configs
container   Manage containers
image       Manage images
network     Manage networks
node        Manage Swarm nodes
plugin      Manage plugins
secret      Manage Docker secrets
service     Manage services
stack       Manage Docker stacks
swarm       Manage Swarm
system      Manage Docker
trust       Manage trust on Docker images
volume      Manage volumes

Commands:
attach      Attach local standard input, output, and error streams to a running container
build       Build an image from a Dockerfile
commit      Create a new image from a container's changes
cp          Copy files/folders between a container and the local filesystem
create      Create a new container
diff        Inspect changes to files or directories on a container's filesystem
events      Get real time events from the server
exec        Run a command in a running container
export      Export a container's filesystem as a tar archive
history     Show the history of an image
images      List images
import      Import the contents from a tarball to create a filesystem image
info        Display system-wide information
inspect     Return low-level information on Docker objects
kill        Kill one or more running containers
load        Load an image from a tar archive or STDIN
login       Log in to a Docker registry
logout      Log out from a Docker registry
logs        Fetch the logs of a container
pause       Pause all processes within one or more containers
port        List port mappings or a specific mapping for the container
ps          List containers
pull        Pull an image or a repository from a registry
push        Push an image or a repository to a registry
rename      Rename a container
restart     Restart one or more containers
rm          Remove one or more containers
rmi         Remove one or more images
run         Run a command in a new container
save        Save one or more images to a tar archive (streamed to STDOUT by default)
search      Search the Docker Hub for images
start       Start one or more stopped containers
stats       Display a live stream of container(s) resource usage statistics
stop        Stop one or more running containers
tag         Create a tag TARGET_IMAGE that refers to SOURCE_IMAGE
top         Display the running processes of a container
unpause     Unpause all processes within one or more containers
update      Update configuration of one or more containers
version     Show the Docker version information
wait        Block until one or more containers stop, then print their exit codes

Run 'docker COMMAND --help' for more information on a command.
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To check the Docker information, use "docker info" command:

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root@ubuntu1804-64b:~# docker info
Containers: 1
Running: 0
Paused: 0
Stopped: 1
Images: 1
Server Version: 18.06.1-ce
Storage Driver: overlay2
Backing Filesystem: extfs
Supports d_type: true
Native Overlay Diff: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
Volume: local
Network: bridge host macvlan null overlay
Log: awslogs fluentd gcplogs gelf journald json-file logentries splunk syslog
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Init Binary: docker-init
containerd version: 468a545b9edcd5932818eb9de8e72413e616e86e
runc version: 69663f0bd4b60df09991c08812a60108003fa340
init version: fec3683
Security Options:
apparmor
seccomp
Profile: default
Kernel Version: 4.15.0-38-generic
Operating System: Ubuntu 18.04.1 LTS
OSType: linux
Architecture: x86_64
CPUs: 1
Total Memory: 985.5MiB
Name: ubuntu1804-64b
ID: OQNX:3QZC:W5BO:CLLP:KXS6:6IOZ:JDXL:C44B:H5BI:CRPJ:HMIX:JQRU
Docker Root Dir: /var/lib/docker
Debug Mode (client): false
Debug Mode (server): false
Registry: https://index.docker.io/v1/
Labels:
Experimental: false
Insecure Registries:
127.0.0.0/8
Live Restore Enabled: false

WARNING: No swap limit support
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To check the Docker version, use "docker version" command:

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root@ubuntu1804-64b:~# docker version
Client:
Version:           18.06.1-ce
API version:       1.38
Go version:        go1.10.3
Git commit:        e68fc7a
Built:             Tue Aug 21 17:24:51 2018
OS/Arch:           linux/amd64
Experimental:      false

Server:
Engine:
Version:          18.06.1-ce
API version:      1.38 (minimum version 1.12)
Go version:       go1.10.3
Git commit:       e68fc7a
Built:            Tue Aug 21 17:23:15 2018
OS/Arch:          linux/amd64
Experimental:     false
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How to work with Docker images?

To search for available Docker images, use "docker search" command. For example, to list down available images for Ubuntu, use "docker search ubuntu" command. For example:

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root@ubuntu1804-64b:~# docker search ubuntu
NAME                                                   DESCRIPTION                                     STARS               OFFICIAL            AUTOMATED
ubuntu                                                 Ubuntu is a Debian-based Linux operating sys…   8626                [OK]
dorowu/ubuntu-desktop-lxde-vnc                         Ubuntu with openssh-server and NoVNC            233                                     [OK]
rastasheep/ubuntu-sshd                                 Dockerized SSH service, built on top of offi…   178                                     [OK]
consol/ubuntu-xfce-vnc                                 Ubuntu container with "headless" VNC session…   131                                     [OK]
ansible/ubuntu14.04-ansible                            Ubuntu 14.04 LTS with ansible                   95                                      [OK]
ubuntu-upstart                                         Upstart is an event-based replacement for th…   92                  [OK]
neurodebian                                            NeuroDebian provides neuroscience research s…   54                  [OK]
1and1internet/ubuntu-16-nginx-php-phpmyadmin-mysql-5   ubuntu-16-nginx-php-phpmyadmin-mysql-5          47                                      [OK]
ubuntu-debootstrap                                     debootstrap --variant=minbase --components=m…   40                  [OK]
nuagebec/ubuntu                                        Simple always updated Ubuntu docker images w…   23                                      [OK]
tutum/ubuntu                                           Simple Ubuntu docker images with SSH access     18
i386/ubuntu                                            Ubuntu is a Debian-based Linux operating sys…   14
1and1internet/ubuntu-16-apache-php-7.0                 ubuntu-16-apache-php-7.0                        13                                      [OK]
ppc64le/ubuntu                                         Ubuntu is a Debian-based Linux operating sys…   12
1and1internet/ubuntu-16-nginx-php-5.6-wordpress-4      ubuntu-16-nginx-php-5.6-wordpress-4             6                                       [OK]
eclipse/ubuntu_jdk8                                    Ubuntu, JDK8, Maven 3, git, curl, nmap, mc, …   6                                       [OK]
codenvy/ubuntu_jdk8                                    Ubuntu, JDK8, Maven 3, git, curl, nmap, mc, …   5                                       [OK]
darksheer/ubuntu                                       Base Ubuntu Image -- Updated hourly             4                                       [OK]
pivotaldata/ubuntu                                     A quick freshening-up of the base Ubuntu doc…   2
smartentry/ubuntu                                      ubuntu with smartentry                          1                                       [OK]
1and1internet/ubuntu-16-sshd                           ubuntu-16-sshd                                  1                                       [OK]
ossobv/ubuntu                                          Custom ubuntu image from scratch (based on o…   0
paasmule/bosh-tools-ubuntu                             Ubuntu based bosh-cli                           0                                       [OK]
1and1internet/ubuntu-16-healthcheck                    ubuntu-16-healthcheck                           0                                       [OK]
pivotaldata/ubuntu-gpdb-dev                            Ubuntu images for GPDB development              0
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To pull an image, use "docker pull" command. For example, if you want to pull the official Ubuntu image:

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root@ubuntu1804-64b:~# docker pull ubuntu
Using default tag: latest
latest: Pulling from library/ubuntu
473ede7ed136: Pull complete
c46b5fa4d940: Pull complete
93ae3df89c92: Pull complete
6b1eed27cade: Pull complete
Digest: sha256:29934af957c53004d7fb6340139880d23fb1952505a15d69a03af0d1418878cb
Status: Downloaded newer image for ubuntu:latest
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To list down all the Docker images currently on your servelet, use "docker images" command. For example:

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root@ubuntu1804-64b:~# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
ubuntu              latest              ea4c82dcd15a        12 days ago         85.8MB
hello-world         latest              4ab4c602aa5e        7 weeks ago         1.84kB
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How to work with Docker containers?

To check the list of Docker containers which are running on your servelet, use "docker ps" command:

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root@ubuntu1804-64b:~# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
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You can see that there's no containers running yet. To list down all the available containers on your servelet, even though it's not running, use "-l" option on "docker ps" command:

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root@ubuntu1804-64b:~# docker ps -l
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
01bab47a9faf hello-world "/hello" 3 hours ago Exited (0) 3 hours ago pedantic_knuth
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Let's try to run the hello-world container. Use "docker run hello-world" command. For example:

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root@ubuntu1804-64b:~# docker run hello-world

Hello from Docker!
This message shows that your installation appears to be working correctly.

To generate this message, Docker took the following steps:
1. The Docker client contacted the Docker daemon.
2. The Docker daemon pulled the "hello-world" image from the Docker Hub.
    (amd64)
3. The Docker daemon created a new container from that image which runs the
    executable that produces the output you are currently reading.
4. The Docker daemon streamed that output to the Docker client, which sent it
    to your terminal.

To try something more ambitious, you can run an Ubuntu container with:
$ docker run -it ubuntu bash

Share images, automate workflows, and more with a free Docker ID:
https://hub.docker.com/

For more examples and ideas, visit:
https://docs.docker.com/get-started/
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How can I get more information on how to use Docker?

You may refer to Docker official documentation, which can be found on below URL:

https://docs.docker.com/
https://docs.docker.com/engine/installation/linux/ubuntulinux/

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