Merge pull request #1552 from ArthurHoaro/feature/better-initializer

[github/shaarli/Shaarli.git] / doc / md / docker / docker-101.md

diff --git a/doc/md/docker/docker-101.md b/doc/md/docker/docker-101.md
index b02dd149a8be61974cb4469ecb0327217d0c3fb0..a9c00b85cbda8c246855934ec7b74dcc856ae26c 100644 (file)
--- a/doc/md/docker/docker-101.md
+++ b/doc/md/docker/docker-101.md
@@ -60,3 +60,81 @@ wheezy: Pulling from debian
 Digest: sha256:c584131da2ac1948aa3e66468a4424b6aea2f33acba7cec0b631bdb56254c4fe
 Status: Downloaded newer image for debian:wheezy
 ```
+
+Docker re-uses layers already downloaded. In other words if you have images based on Alpine or some Ubuntu version for example, those can share disk space.
+
+### Start a container
+A container is an instance created from an image, that can be run and that keeps running until its main process exits. Or until the user stops the container. 
+
+The simplest way to start a container from image is ``docker run``. It also pulls the image for you if it is not locally available. For more advanced use, refer to ``docker create``.
+
+Stopped containers are not destroyed, unless you specify ``--rm``. To view all created, running and stopped containers, enter:
+```bash
+$ docker ps -a
+```
+
+Some containers may be designed or configured to be restarted, others are not. Also remember both network ports and volumes of a container are created on start, and not editable later.
+
+### Access a running container
+A running container is accessible using ``docker exec``, or ``docker copy``. You can use ``exec`` to start a root shell in the Shaarli container:
+```bash
+$ docker exec -ti <container-name-or-id> bash
+```
+Note the names and ID's of containers are listed in ``docker ps``. You can even type only one or two letters of the ID, given they are unique.
+
+Access can also be through one or more network ports, or disk volumes. Both are specified on and fixed on ``docker create`` or ``run``.
+
+You can view the console output of the main container process too:
+```bash
+$ docker logs -f <container-name-or-id>
+```
+
+### Docker disk use
+Trying out different images can fill some gigabytes of disk quickly. Besides images, the docker volumes usually take up most disk space.
+
+If you care only about trying out docker and not about what is running or saved, the following commands should help you out quickly if you run low on disk space:
+
+```bash
+$ docker rmi -f $(docker images -aq) # remove or mark all images for disposal
+$ docker volume rm $(docker volume ls -q) # remove all volumes
+```
+
+### Systemd config
+Systemd is the process manager of choice on Debian-based distributions. Once you have a ``docker`` service installed, you can use the following steps to set up Shaarli to run on system start.
+
+```bash
+systemctl enable /etc/systemd/system/docker.shaarli.service
+systemctl start docker.shaarli
+systemctl status docker.*
+journalctl -f # inspect system log if needed
+```
+
+You will need sudo or a root terminal to perform some or all of the steps above. Here are the contents for the service file:
+```
+[Unit]
+Description=Shaarli Bookmark Manager Container
+After=docker.service
+Requires=docker.service
+
+
+[Service]
+Restart=always
+
+# Put any environment you want in an included file, like $host- or $domainname in this example
+EnvironmentFile=/etc/sysconfig/box-environment
+
+# It's just an example..
+ExecStart=/usr/bin/docker run \
+  -p 28010:80 \
+  --name ${hostname}-shaarli \
+  --hostname shaarli.${domainname} \
+  -v /srv/docker-volumes-local/shaarli-data:/var/www/shaarli/data:rw \
+  -v /etc/localtime:/etc/localtime:ro \
+  shaarli/shaarli:latest
+
+ExecStop=/usr/bin/docker rm -f ${hostname}-shaarli
+
+
+[Install]
+WantedBy=multi-user.target
+```