Docker

Latest revision as of 23:16, 8 February 2016

My little page about getting docker to run, done by somebody having no idea what docker is.

Yeah, DAU-docker!

[edit] First install docker

• sudo apt-get install docker.io
• sudo usermod -a -G docker $(id -un)
• # logoout/login to get your group attribution

[edit] Learn something about the docker philosophy

You usually never log in to the container but specify all settings in the Dockerfile. Recreating the container should give you a ready to run application.

Most installs don't care really what happens to your data, but docker has a feature for this. Put the data into a separate container than the application. Then make the data container mount points visible in your application container. This way you can replace the application (update) without needing a backup/restore step.

[edit] Mediawiki

[edit] Fist some settings

• WEBPORT=8080 # on which port the webserver should listen on the main host, if you have already a webserver, 80 won't work
• DBPASSWORD="$(openssl rand -base64 9)" # the password for the database (humm... save it :-)
• DOCKERNAME="mediawiki"

[edit] Create a database

• # inspired from https://hub.docker.com/_/mysql/
• # Create a data container with a directory /var/lib/mysql
• docker create -v /var/lib/mysql --name wiki-mysql-data mysql:latest /bin/true
• docker run --name wiki-mysql --volumes-from wiki-mysql-data -e MYSQL_ROOT_PASSWORD=$DBPASSWORD -d mysql:latest
• docker ps -a | grep wiki-mysql.* # look the nice containers we just did

[edit] Create a mediawiki

well probably something like found here https://hub.docker.com/r/nickstenning/mediawiki/ (with data container support) as stated on that webpage:

• docker run --name $DOCKERNAME --link wiki-mysql:mysql -p $WEBPORT:80 -d nickstenning/mediawiki

[edit] Configure mediawiki

• echo "connect to http://localhost:$WEBPORT/"
• click on "setup the wiki"
  • database host: mysql
  • database name: mysql
  • table prefix: mw #change this if you install more than one mediawiki into this database
  • username: root
  • echo password: $DBPASSWORD
  • at end of setup you get a LocalSettings.php to download
  • this file has to be provided to the docker or put into the container. Seems to be several ways to do it.
• docker stop $DOCKERNAME # stop the container as we want to mount data...
• docker rm $DOCKERNAME # I have no idea how to add parameters, so I just start from zero

[edit] Create wiki data container

• docker create --name ${DOCKERNAME}-data -v /data nickstenning/mediawiki /bin/true
• docker run --name ${DOCKERNAME} --volumes-from ${DOCKERNAME}-data --link wiki-mysql:mysql -p $WEBPORT:80 -d nickstenning/mediawiki
• cat LocalSettings.php | docker exec -i ${DOCKERNAME} sh -c 'cat > /data/LocalSettings.php'
• docker exec -i ${DOCKERNAME} chown www-data:www-data /data/LocalSettings.php
• docker exec -i ${DOCKERNAME} chmod 444 /data/LocalSettings.php

• echo "wiki is on http://localhost:$WEBPORT/index.php"

More help: well the usual mediawiki help

[edit] Engelsystem

This does not use a data container, but as it's often only for a short event, I don't care.

Give some configuration stuff

• ENGELPORT=80 # on which port the engel system should listen on the main host, if you have a webserver, 80 won't work
• ENGELDB=3306 # on which port the mysql of the engelsystem should be visible on the main host
• DBPASSWORD="$(openssl rand -base64 9)" # the password for the database (humm... save it it :-)
• ENGELPASSWORD="$(openssl rand -base64 9)" # the password for the engelsystem (humm... save it it :-)
• DOCKERNAME="engelsystem"
• ENGELADMIN="engeladmin" # well just use it

from https://github.com/ruep/dockerfile-engel

• git clone https://github.com/ruep/dockerfile-engel.git
• cd dockerfile-engel/
• docker build -t engelweb-app . # this takes a long time
• docker run --name "$DOCKERNAME" -d -p ${ENGELPORT}:80 -p ${ENGELDB}:3306 -e MYSQL_PASS="$DBPASSWORD" engelweb-app
• docker exec -t "$DOCKERNAME" sed -i 's/-pengel/-p'$DBPASSWORD'/' /engelweb/db/createdb.sh # needed coz db pass hardcoded
• docker exec -t "$DOCKERNAME" /engelweb/db/createdb.sh engelsystem engeladmin "$ENGELPASSWORD"
• docker exec -t "$DOCKERNAME" sh -c "/usr/bin/mysql -uadmin -p$DBPASSWORD engelsystem < /engelweb/db/install.sql"
• docker exec -t "$DOCKERNAME" sh -c "/usr/bin/mysql -uadmin -p$DBPASSWORD engelsystem < /engelweb/db/update.sql"

• echo "Please remember the database password: $DBPASSWORD"
• echo "Please remember the engelsystem login: ${ENGELADMIN} ${ENGELPASSWORD}"
• echo login to http://localhost:$ENGELPORT/ with user 'admin' and password 'asdfasdf'