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--- linux:docker [2023/05/23 20:17] – created Wulf Rajek
+++ linux:docker [2025/04/16 23:45] (current) – Wulf Rajek
@@ Line 1: / Line 1: @@
 ====== Docker ======
-Copying files from/to images
+https://docs.docker.com/storage/volumes/
+===== Main install =====
 <code>
-docker cp dockerimage/bla ./bla
+apt-get -y install curl unzip dialog
-docker cp ./bla dockerimage/bla
+curl -fSSL get.docker.com | sh
+</code>
+===== Show logs =====
+<code>
+docker logs --follow <containername>
+</code>
+===== Build image =====
+To build the docker image based on a Dockerfile in the current directory, use:
+<code>
+docker build .
+</code>
+===== Update container =====
+Update docker container to latest version via docker compose:
+<code>
+#Single container:
+docker compose pull calibre-web
+docker compose up -d calibre-web
+docker image prune
+#Update all containers:
+docker compose pull
+docker compose up -d
+docker image prune
+</code>
+===== Health Checks =====
+Docker compose health checks:
+https://medium.com/geekculture/how-to-successfully-implement-a-healthcheck-in-docker-compose-efced60bc08e
+https://stefanjarina.gitbooks.io/docker/content/swarm-mode/healthchecks.html
+===== Copying files to/from containers =====
+Copying files from/to containers
+<code>
+docker cp dockerimage:/bla ./bla
+docker cp ./bla dockerimage:/bla
+</code>
+===== Flatten docker image layers =====
+Flatten docker image layers:
+<code>
+FROM yourbuildimage as build
+# your existing build steps here
+FROM scratch
+COPY --from=build / /
+CMD ["/your/start/script"]
+</code>
+===== Change mount points of containers =====
+Change mount points of existing docker containers;
+e.g. mount /home/<user-name> folder of host to the /mnt folder of the existing (not running) container.
+  - stop docker container or whole docker engine <code>systemctl stop docker.service</code>
+  - Open configuration file corresponding to the stopped container, which can be found at /var/lib/docker/containers/99d...1fb/config.v2.json (may be config.json for older versions of docker). For pretty print use <code>vi <(jq . /var/lib/docker/containers/<container-ID>/config.v2.json)
+Save updates to a file: :w config.v2.json
+Exit vim: :q!
+Update existing file: jq -c . config.v2.json > /var/lib/docker/containers/<container-ID>/config.v2.json
+ </code>
+  - Find MountPoints section: "MountPoints":{}.
+  - Replace the contents with something like this (you can copy proper contents from another container with proper settings):<code>
+"MountPoints":{"/mnt":{"Source":"/home/<user-name>","Destination":"/mnt","RW":true,"Name":"","Driver":"","Type":"bind","Propagation":"rprivate","Spec":{"Type":"bind","Source":"/home/<user-name>","Target":"/mnt"},"SkipMountpointCreation":false}}</code> or the same (formatted):<code>
+  "MountPoints": {
+    "/mnt": {
+      "Source": "/home/<user-name>",
+      "Destination": "/mnt",
+      "RW": true,
+      "Name": "",
+      "Driver": "",
+      "Type": "bind",
+      "Propagation": "rprivate",
+      "Spec": {
+        "Type": "bind",
+        "Source": "/home/<user-name>",
+        "Target": "/mnt"
+      },
+      "SkipMountpointCreation": false
+    }
+  }
+</code>
+  - Start or restart the docker service: <code>systemctl start docker.service
+service docker restart</code>
+  - Start the container if necessary: <code>docker start <container-name/ID></code>
+===== PHP&NGINX image =====
+Containerised PHP & NGINX on Alpine, image size ~60MB:
+https://levelup.gitconnected.com/containerizing-nginx-php-fpm-on-alpine-linux-953430ea6dbc
+https://github.com/johnathanesanders/docker-nginx-fpm
+Log nginx to stdout in Dockerfile:
+<code>
+# forward request and error logs to docker log collector
+RUN ln -sf /dev/stdout /var/log/nginx/access.log \
+	&& ln -sf /dev/stderr /var/log/nginx/error.log
+</code>
+===== Rename/Retag image files =====
+<code>
+docker tag current/image:tag new/image:tag
+</code>
+===== cmd shell of container =====
+<code>
+docker exec -it <mycontainer> bash
+docker exec -it <mycontainer> /bin/sh
+</code>
+===== GPU hardware acceleration =====
+Make sure the relevant GPU drivers are installed on the base system, then pass through the device via docker compose.
+Check devices are available, there should be a device per GPU starting at renderD128 for the first GPU:
+<code>
+ls -la /dev/dri
+</code>
+<code>
+  devices:
+   - /dev/dri:/dev/dri
+</code>
+===== docker ps short =====
+Short form of docker ps to only get the container names:
+<code>
+docker ps | sed 's/   */#/g' | cut -d "#" -f 7
+</code>
+===== docker running out of network addresses =====
+Error response from daemon: all predefined address pools have been fully subnetted
+<code json /etc/docker/daemon.json>
+{
+"default-address-pools":[
+    {"base":"169.254.2.0/23","size":28},
+    {"base":"169.254.4.0/22","size":28},
+    {"base":"169.254.8.0/21","size":28},
+    {"base":"169.254.16.0/20","size":28},
+    {"base":"169.254.32.0/19","size":28},
+    {"base":"169.254.64.0/18","size":28},
+    {"base":"169.254.128.0/18","size":28},
+    {"base":"169.254.192.0/19","size":28},
+    {"base":"169.254.224.0/20","size":28},
+    {"base":"169.254.240.0/21","size":28},
+    {"base":"169.254.248.0/22","size":28}
+  ]
+}
+</code>
+<code>
+docker restart
+docker network prune
 </code>