Azure File Storage as a Docker Plugin

Docker Mar 11, 2018

Azure File is a Docker Volume Driver which uses Azure File Storage
to mount file shares on the cloud to Docker containers as volumes. It uses network
file sharing (SMB/CIFS protocols) capabilities of Azure File Storage.

Why?

  • You can create Docker containers that can migrate from one host to another seamlessly.
  • You can share volumes among multiple containers running on different hosts.

Usage

Before deploying this plugin, please read articles:

and be aware of the above limitations and what kind of applications are suitable for storing data on Azure File Service.

In addition of previous limitation, Azure File doesn't support the samba unix extention. Without this extention, the filesystem will not support hard link (used by postgres WAL for example), and other unix flavored features.

Installation

Make sure you have a Storage Account on Azure (using Azure CLI or Portal).

Docker managed plugin may be installed with following command:

$ docker plugin install jmaitrehenry/azurefile[:version] \
    AZURE_STORAGE_ACCOUNT=xxx \
    AZURE_STORAGE_ACCOUNT_KEY=yyy

The [:version] component in the above command is known as a Docker tag and its value follows the semantic versioning model. Omitting the version is equivalent to specifying the latest tag -- the most recent, stable version of a plug-in.

Example

Create volumes

Starting from Docker 1.9+ you can create volumes and containers as follows:

$ docker volume create --name my_volume -d jmaitrehenry/azurefile

This will create an Azure File Share named my_volume (if it does not exist).

You can specify additional volume options to customize the owner, group, and permissions for files and directories.
See the mount.cifs(8) man page more details on these options.

Mount Options Available:

  • uid
  • gid
  • filemode
  • dirmode
  • cache
  • nolock
  • nobrl
  • remotepath
$ docker volume create -d jmaitrehenry/azurefile \
  -o share=sharename \
  -o uid=999 \
  -o gid=999 \
  -o filemode=0600 \
  -o dirmode=0755 \
  -o nolock=true \
  -o remotepath=directory
  my_volume

Note: On a stack file, the filemode and dirmode must be pass as a string (between quote).

Use a volume

The following example illustrates using a volume:

$ docker run -i -t -v my_volume:/data busybox

Docker will start a container in which you can use /data directory to directly read/write from cloud file share location using SMB protocol.

Remove a volume

The following example illustrates removing a volume created:

$ docker volume rm my_volume

If you find a typo, have a problem when trying what you find on this article, please contact me!

Tags

Julien Maitrehenry

I specialize in DevOps, Agile practices and web development. I love sharing my knowledge for helping other people to go to the next level!