Docker

Docker is a container platform.

It's open source but if you go to the site, you won't be able to tell, you can just find out about pricing there. After looking at docker.com, go to https://github.com/docker/docker and look for installation instructions there.

I am following their instructions to install on two Debian systems, one co-located and one at home.

I want to set up containers for Geonode and Geoserver.

I know how fiddly Geoserver can be (it runs in Tomcat) and so I want to isolate it from the Debian host it will run on.

I already have PostgreSQL 9.5 running directly on the host, but my only intended use is as a backend for PostGIS/Geoserver, so I will probably follow along with the instructions here and containerize it too.

So in preparation for using Docker. I removed PostgreSQL and Tomcat from my host server.

Orchestrating Geoserver with Docker and Fig

I have no idea what Fig is, yet.

Development on Mac

Set up a Vagrant machine to run an instance of MySQL. Make sure it has port 3306 open and set a root password. Install Docker for Mac and Kitematic.

Docker Hub

apt-get install docker-engine

Metadata

Get an id:

docker ps

Look at a container in detail

docker inspect id

See also /var/lib/docker/containers/id

Docker networking

Check ifconfig docker0 to see what the bridge address is on your docker server then as needed create a route on your router so that traffic can flow from your local computers into the docker instances running on the docker server.

If you have more than one docker server you have to make sure they don't both pick the same network ip range. If routes are already set up in the router docker should be able to find an unused subnet.

docker pull nginx

cd static-html-directory cat <<EOF > nginx.docker FROM nginx COPY static-html-directory /usr/share/nginx/html EOF

Place this file in the same directory as your directory of content ("static-html-directory"), run ., then start your container:

docker run --name some-nginx -d some-content-nginx

Owncloud

I want to run Owncloud, so I need these components

1. Nginx (nginx)
2. php 7 vinaocruz/php7-fpm-mysql
3. Redis redis
4. Owncloud (Owncloud is just some files so it does not need a separate docker container)
5. MySQL (which runs on the host not in Docker)

Redis

Used by owncloud (via PHP) and by nginx. It needs some file space.

docker run --name redis-owncloud -d redis redis-server --appendonly yes

I need to learn more about persistent data.

php7-fpm-mysql

This Docker exposes port 9000 and it is based on Debian. Has both php server and cli php in it.

Using FPM uncouples PHP from the web server (and lets nginx run php code which it otherwise cannot do.) It's like FastCGI if you know what that is. It runs PHP as a separate service, so it can be in a separate Docker.

• It needs to be able to find the owncloud PHP. I think the code gets passed into it from nginx so there is nothing special to do here. Just link the fpm and nginx dockers together.

Nginx

• It needs to know about Redis.
• It needs to be able to find the owncloud files.

Linking it all together

Server: MySQL Create an owncloud database, with a user owncloud allowed full access to the database. Make sure that the Nginx server can connect to it through the private LAN. (I run MySQL on the Docker host.)

Source: Redis Start the Redis docker as a source

Source: PHP7 Start the FPM PHP7 docker as a source

Receiver: Nginx Start the Nginx docker as a receiver for the services from Redis and PHP7. Add environment settings to tell it how to find MySQL.