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diff --git a/doc/md/docker/docker-101.md b/doc/md/docker/docker-101.md index b02dd149..a9c00b85 100644 --- a/doc/md/docker/docker-101.md +++ b/doc/md/docker/docker-101.md | |||
@@ -60,3 +60,81 @@ wheezy: Pulling from debian | |||
60 | Digest: sha256:c584131da2ac1948aa3e66468a4424b6aea2f33acba7cec0b631bdb56254c4fe | 60 | Digest: sha256:c584131da2ac1948aa3e66468a4424b6aea2f33acba7cec0b631bdb56254c4fe |
61 | Status: Downloaded newer image for debian:wheezy | 61 | Status: Downloaded newer image for debian:wheezy |
62 | ``` | 62 | ``` |
63 | |||
64 | 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. | ||
65 | |||
66 | ### Start a container | ||
67 | 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. | ||
68 | |||
69 | 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``. | ||
70 | |||
71 | Stopped containers are not destroyed, unless you specify ``--rm``. To view all created, running and stopped containers, enter: | ||
72 | ```bash | ||
73 | $ docker ps -a | ||
74 | ``` | ||
75 | |||
76 | 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. | ||
77 | |||
78 | ### Access a running container | ||
79 | A running container is accessible using ``docker exec``, or ``docker copy``. You can use ``exec`` to start a root shell in the Shaarli container: | ||
80 | ```bash | ||
81 | $ docker exec -ti <container-name-or-id> bash | ||
82 | ``` | ||
83 | 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. | ||
84 | |||
85 | Access can also be through one or more network ports, or disk volumes. Both are specified on and fixed on ``docker create`` or ``run``. | ||
86 | |||
87 | You can view the console output of the main container process too: | ||
88 | ```bash | ||
89 | $ docker logs -f <container-name-or-id> | ||
90 | ``` | ||
91 | |||
92 | ### Docker disk use | ||
93 | Trying out different images can fill some gigabytes of disk quickly. Besides images, the docker volumes usually take up most disk space. | ||
94 | |||
95 | 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: | ||
96 | |||
97 | ```bash | ||
98 | $ docker rmi -f $(docker images -aq) # remove or mark all images for disposal | ||
99 | $ docker volume rm $(docker volume ls -q) # remove all volumes | ||
100 | ``` | ||
101 | |||
102 | ### Systemd config | ||
103 | 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. | ||
104 | |||
105 | ```bash | ||
106 | systemctl enable /etc/systemd/system/docker.shaarli.service | ||
107 | systemctl start docker.shaarli | ||
108 | systemctl status docker.* | ||
109 | journalctl -f # inspect system log if needed | ||
110 | ``` | ||
111 | |||
112 | 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: | ||
113 | ``` | ||
114 | [Unit] | ||
115 | Description=Shaarli Bookmark Manager Container | ||
116 | After=docker.service | ||
117 | Requires=docker.service | ||
118 | |||
119 | |||
120 | [Service] | ||
121 | Restart=always | ||
122 | |||
123 | # Put any environment you want in an included file, like $host- or $domainname in this example | ||
124 | EnvironmentFile=/etc/sysconfig/box-environment | ||
125 | |||
126 | # It's just an example.. | ||
127 | ExecStart=/usr/bin/docker run \ | ||
128 | -p 28010:80 \ | ||
129 | --name ${hostname}-shaarli \ | ||
130 | --hostname shaarli.${domainname} \ | ||
131 | -v /srv/docker-volumes-local/shaarli-data:/var/www/shaarli/data:rw \ | ||
132 | -v /etc/localtime:/etc/localtime:ro \ | ||
133 | shaarli/shaarli:latest | ||
134 | |||
135 | ExecStop=/usr/bin/docker rm -f ${hostname}-shaarli | ||
136 | |||
137 | |||
138 | [Install] | ||
139 | WantedBy=multi-user.target | ||
140 | ``` | ||