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=Overview=
==What is Docker==
Docker is a way of deploying apps on servers. It packages apps into side-by-side containers. These are similar in spirit to virtual machines, but different because containers are not (or, don't have to be) fully bundled operating systems. The container system makes sure everything runs the same everywhere.  
Docker is a way of deploying apps on servers. It packages apps into side-by-side containers. These are similar in spirit to virtual machines, but different because containers are not (or, don't have to be) fully bundled operating systems. The container system makes sure everything runs the same everywhere.  


It's like [[Homebrew]] or [[Aptitude]] for apps.
It's like [[Homebrew]] or [[Aptitude]] for apps.


=Installing=
[[Docker/Troubleshooting]]
 
Docker has great documentation on getting up and running: https://docs.docker.com/
 
Docker also provides several examples of docker-izing an app: https://docs.docker.com/engine/examples/
 
==Ubuntu Linux==
 
You can get docker running on many virtual hosting services.
 
Linode supports docker: https://blog.linode.com/2014/01/03/docker-on-linode/
 
They offer installation guides for different distributions: https://docs.docker.com/engine/installation/linux/#install-using-the-repository
 
Guide to installing Docker on Ubuntu Linux: https://docs.docker.com/engine/installation/linux/ubuntulinux/
 
Start by setting up Docker's repositories:
 
<pre>
$ sudo apt-get install \
    apt-transport-https \
    ca-certificates \
    curl \
    software-properties-common
</pre>
 
Add Docker's GPG key:
 
<pre>
$ curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
</pre>
 
Verify fingerprint starts with 9DC8:
 
<pre>
$ sudo apt-key fingerprint 0EBFCD88
</pre>
 
Set up the stable repository:
 
<pre>
$ sudo add-apt-repository \
  "deb [arch=amd64] https://download.docker.com/linux/ubuntu \
  $(lsb_release -cs) \
  stable"
</pre>
 
Install docker by updating package index and running install:
 
<pre>
$ sudo apt-get update
$ sudo apt-get install docker-ce
</pre>
 
Test it out:
 
<pre>
$ sudo docker run hello-world
</pre>
 
 
 
===Errors===
 
When I added Docker's repos to my aptitude following the instructions above, I kept seeing 403 errors from docker's repo when I ran apt-get update:
 
<pre>
sudo apt-get update
...
W: Failed to fetch https://download.docker.com/linux/ubuntu/dists/wily/stable/binary-amd64/Packages  HttpError403
 
</pre>
 
Yuck. Others have had this issue too. [https://github.com/docker/docker/issues/31940]
 
===Resolving===
 
Resolved the problem by visiting their apt repos with a browser and manually downloading/installing the .deb file.
 
Start with the name of your release:
 
<pre>
$ lsb_release -c
Codename:                    wily
</pre>
 
Now navigate to their aptitude repositories in your browser: https://apt.dockerproject.org/repo/pool/main/d/docker-engine/
 
Find the deb file that corresponds to your install and copy the link.
 
<pre>
$ wget <link to .deb file>
</pre>
 
Now you can install it (you probably need to be sudo):
 
<pre>
$ dpkg -i docker-engine_1.9.1-0~wily_amd64.deb
Selecting previously unselected package docker-engine.
(Reading database ... 142272 files and directories currently installed.)
Preparing to unpack docker-engine_1.9.1-0~wily_amd64.deb ...
Unpacking docker-engine (1.9.1-0~wily) ...
Setting up docker-engine (1.9.1-0~wily) ...
Processing triggers for ureadahead (0.100.0-19) ...
Processing triggers for systemd (225-1ubuntu9.1) ...
Processing triggers for man-db (2.7.4-1) ...
</pre>
 
==Mac==
 
You can run docker on Mac: https://docs.docker.com/docker-for-mac/
 
 
==Docker on Linux Without Sudo==
 
To modify Docker so it runs on Linux without requiring the use of the sudo command, create a docker group:
 
<pre>
groupadd docker
usermod -a -G docker username
</pre>
 
That's it - boom - you should be able to run the docker hello world without sudo:
 
<pre>
$ docker hello-world # look ma, no sudo
</pre>
 
=Up and Running=
 
post installation info: https://docs.docker.com/engine/installation/linux/linux-postinstall/#upstart
 
==Test==
 
Test you are up and running with a working install of docker:
 
<pre>
$ docker --version
Docker version 17.03.0-ce, build 60ccb22
 
$ docker-compose --version
docker-compose version 1.11.2, build dfed245
 
$ docker-machine --version
docker-machine version 0.10.0, build 76ed2a6
 
$ docker version
Client:
Version:      1.9.1
API version:  1.21
Go version:  go1.4.2
Git commit:  a34a1d5
Built:        Fri Nov 20 13:20:08 UTC 2015
OS/Arch:      linux/amd64
Cannot connect to the Docker daemon. Is the docker daemon running on this host?
</pre>
 
==Hello world==
 
<pre>
$ sudo docker run hello-world
Unable to find image 'hello-world:latest' locally
latest: Pulling from hello-world
 
50a54e1f9180: Pull complete
7a5a2d73abce: Pull complete
Digest: sha256:7820f4620e6cf3e795643fac2f6b09e7fd0a29e7e5c4eee6aac9ba0bedca158c
Status: Downloaded newer image for hello-world:latest
 
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.
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:
[[Docker/Network Debugging]]
https://cloud.docker.com/


For more examples and ideas, visit:
=References=
https://docs.docker.com/engine/userguide/


Docker's documentation is excellent: https://docs.docker.com/


</pre>
Docker from the command line: https://docs.docker.com/engine/reference/commandline/cli/


==web server==
Docker to run memcached (Digital Ocean guide): https://www.digitalocean.com/community/tutorials/docker-explained-how-to-create-docker-containers-running-memcached


<pre>
Note that many Docker issues on Github contain a wealth of useful debugging strategies and commands for checking the state of networks, ports, etc. Example: https://github.com/docker/docker/issues/13914
docker run -d -p 80:80 --name webserver nginx
</pre>


Potential security issues with Docker containers: https://blog.docker.com/2013/08/containers-docker-how-secure-are-they/


=Security Notes=
=Flags=


Being in the docker group gives you serious root-level powers. Info about attack surface of Docker: https://docs.docker.com/engine/security/security/#docker-daemon-attack-surface
{{DockerFlag}}

Latest revision as of 09:40, 28 February 2018

Docker is a way of deploying apps on servers. It packages apps into side-by-side containers. These are similar in spirit to virtual machines, but different because containers are not (or, don't have to be) fully bundled operating systems. The container system makes sure everything runs the same everywhere.

It's like Homebrew or Aptitude for apps.

Docker/Troubleshooting

Docker/Network Debugging

References

Docker's documentation is excellent: https://docs.docker.com/

Docker from the command line: https://docs.docker.com/engine/reference/commandline/cli/

Docker to run memcached (Digital Ocean guide): https://www.digitalocean.com/community/tutorials/docker-explained-how-to-create-docker-containers-running-memcached

Note that many Docker issues on Github contain a wealth of useful debugging strategies and commands for checking the state of networks, ports, etc. Example: https://github.com/docker/docker/issues/13914

Potential security issues with Docker containers: https://blog.docker.com/2013/08/containers-docker-how-secure-are-they/

Flags


Docker.png
docker
notes on the virtual microservice container platform

Docker

Installing the docker platform: Docker/Installing

Docker Hello World: Docker/Hello World


Creating Docker Containers:

Getting docker containers from docker hub: Docker/Dockerhub

Creating docker containers with dockerfiles: Docker/Dockerfiles

Managing Dockerfiles using git: Docker/Dockerfiles/Git

Setting up Python virtualenv in container: Docker/Virtualenv


Running Docker Containers:

Running docker containers: Docker/Basics

Dealing with volumes in Docker images: Docker/Volumes

Removing Docker images: Docker/Removing Images

Rsync Docker Container: Docker/Rsync


Networking with Docker Containers:

Docker/Networking




Flags  · Template:DockerFlag  · e




Docker.png
docker pods
pods are groups of docker containers that travel together

Docker pods are collections of Docker containers that are intended to run in concert for various applications.


Wireless Sensor Data Acquisition Pod

Docker/Pods/Wifi

The wireless sensor data acquisition pod deploys containers
to allow Raspberry Pis to transfer sensor data over wireless networks
by establishing secure SSL tunnels out of the network.

This pod uses the following technologies:

Stunnel  · Rsync  · Apache  · MongoDB  · Python  · Jupyter (numerical Python stack)


Deep Learning Pod

Docker/Pods/Deep Learning

This pod utilizes the following technologies:

Python  · Sklearn  · Jupyter (numerical Python stack)  · Keras  · TensorFlow


Flags  · Template:DockerPodsFlag  · e



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