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+---
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+description: Volume plugin for Amazon EBS
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+keywords: "API, Usage, plugins, documentation, developer, amazon, ebs, rexray, volume"
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+title: Volume plugin for Amazon EBS
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+---
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+
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+<!-- This file is maintained within the docker/docker Github
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+ repository at https://github.com/docker/docker/. Make all
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+ pull requests against that repo. If you see this file in
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+ another repository, consider it read-only there, as it will
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+ periodically be overwritten by the definitive file. Pull
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+ requests which include edits to this file in other repositories
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+ will be rejected.
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+-->
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+
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+# A proof-of-concept Rexray plugin
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+
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+In this example, a simple Rexray plugin will be created for the purposes of using
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+it on an Amazon EC2 instance with EBS. It is not meant to be a complete Rexray plugin.
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+
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+The example source is available at [https://github.com/tiborvass/rexray-plugin](https://github.com/tiborvass/rexray-plugin).
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+
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+To learn more about Rexray: [https://github.com/codedellemc/rexray](https://github.com/codedellemc/rexray)
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+
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+## 1. Make a Docker image
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+
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+The following is the Dockerfile used to containerize rexray.
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+
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+```Dockerfile
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+FROM debian:jessie
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+RUN apt-get update && apt-get install -y --no-install-recommends wget ca-certificates
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+RUN wget https://dl.bintray.com/emccode/rexray/stable/0.6.4/rexray-Linux-x86_64-0.6.4.tar.gz -O rexray.tar.gz && tar -xvzf rexray.tar.gz -C /usr/bin && rm rexray.tar.gz
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+RUN mkdir -p /run/docker/plugins /var/lib/libstorage/volumes
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+ENTRYPOINT ["rexray"]
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+CMD ["--help"]
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+```
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+
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+To build it you can run `image=$(cat Dockerfile | docker build -q -)` and `$image`
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+will reference the containerized rexray image.
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+
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+## 2. Extract rootfs
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+
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+```sh
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+$ TMPDIR=/tmp/rexray # for the purpose of this example
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+$ # create container without running it, to extract the rootfs from image
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+$ docker create --name rexray "$image"
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+$ # save the rootfs to a tar archive
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+$ docker export -o $TMPDIR/rexray.tar rexray
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+$ # extract rootfs from tar archive to a rootfs folder
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+$ ( mkdir -p $TMPDIR/rootfs; cd $TMPDIR/rootfs; tar xf ../rexray.tar )
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+```
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+
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+## 3. Add plugin configuration
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+
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+We have to put the following JSON to `$TMPDIR/config.json`:
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+
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+```json
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+{
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+ "Args": {
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+ "Description": "",
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+ "Name": "",
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+ "Settable": null,
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+ "Value": null
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+ },
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+ "Description": "A proof-of-concept EBS plugin (using rexray) for Docker",
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+ "Documentation": "https://github.com/tiborvass/rexray-plugin",
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+ "Entrypoint": [
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+ "/usr/bin/rexray", "service", "start", "-f"
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+ ],
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+ "Env": [
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+ {
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+ "Description": "",
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+ "Name": "REXRAY_SERVICE",
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+ "Settable": [
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+ "value"
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+ ],
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+ "Value": "ebs"
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+ },
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+ {
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+ "Description": "",
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+ "Name": "EBS_ACCESSKEY",
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+ "Settable": [
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+ "value"
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+ ],
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+ "Value": ""
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+ },
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+ {
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+ "Description": "",
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+ "Name": "EBS_SECRETKEY",
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+ "Settable": [
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+ "value"
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+ ],
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+ "Value": ""
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+ }
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+ ],
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+ "Interface": {
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+ "Socket": "rexray.sock",
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+ "Types": [
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+ "docker.volumedriver/1.0"
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+ ]
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+ },
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+ "Linux": {
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+ "AllowAllDevices": true,
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+ "Capabilities": ["CAP_SYS_ADMIN"],
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+ "Devices": null
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+ },
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+ "Mounts": [
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+ {
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+ "Source": "/dev",
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+ "Destination": "/dev",
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+ "Type": "bind",
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+ "Options": ["rbind"]
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+ }
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+ ],
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+ "Network": {
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+ "Type": "host"
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+ },
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+ "PropagatedMount": "/var/lib/libstorage/volumes",
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+ "User": {},
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+ "WorkDir": ""
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+}
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+```
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+
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+Please note a couple of points:
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+- `PropagatedMount` is needed so that the docker daemon can see mounts done by the
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+rexray plugin from within the container, otherwise the docker daemon is not able
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+to mount a docker volume.
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+- The rexray plugin needs dynamic access to host devices. For that reason, we
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+have to give it access to all devices under `/dev` and set `AllowAllDevices` to
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+true for proper access.
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+- The user of this simple plugin can change only 3 settings: `REXRAY_SERVICE`,
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+`EBS_ACCESSKEY` and `EBS_SECRETKEY`. This is because of the reduced scope of this
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+plugin. Ideally other rexray parameters could also be set.
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+
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+## 4. Create plugin
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+
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+`docker plugin create tiborvass/rexray-plugin "$TMPDIR"` will create the plugin.
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+
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+```sh
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+$ docker plugin ls
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+ID NAME DESCRIPTION ENABLED
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+2475a4bd0ca5 tiborvass/rexray-plugin:latest A rexray volume plugin for Docker false
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+```
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+
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+## 5. Test plugin
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+
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+```sh
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+$ docker plugin set tiborvass/rexray-plugin EBS_ACCESSKEY=$AWS_ACCESSKEY EBS_SECRETKEY=$AWS_SECRETKEY`
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+$ docker plugin enable tiborvass/rexray-plugin
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+$ docker volume create -d tiborvass/rexray-plugin my-ebs-volume
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+$ docker volume ls
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+DRIVER VOLUME NAME
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+tiborvass/rexray-plugin:latest my-ebs-volume
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+$ docker run --rm -v my-ebs-volume:/volume busybox sh -c 'echo bye > /volume/hi'
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+$ docker run --rm -v my-ebs-volume:/volume busybox cat /volume/hi
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+bye
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+```
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+
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+## 6. Push plugin
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+
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+First, ensure you are logged in with `docker login`. Then you can run:
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+`docker plugin push tiborvass/rexray-plugin` to push it like a regular docker
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+image to a registry, to make it available for others to install via
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+`docker plugin install tiborvass/rexray-plugin EBS_ACCESSKEY=$AWS_ACCESSKEY EBS_SECRETKEY=$AWS_SECRETKEY`.
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Tibor Vass