Docker LVM Plugin

Docker Volume Driver for LVM volumes packaged as a Docker Plugin: see https://github.com/containers/docker-lvm-plugin.

This plugin can be used to create lvm volumes of specified size, which can then be bind mounted into the container using docker run command.

Setup

Edit /etc/docker/docker-lvm-plugin and set the volume group to create volumes in.

Install (and enable) the plugin

docker plugin install nickbreen/docker-lvm-plugin

The docker-lvm-plugin also supports the creation of thinly-provisioned volumes. To create a thinly-provisioned volume, a user (administrator) must first create a thin pool using the lvcreate command.

lvcreate -L 10G -T vg1/mythinpool

This will create a thinpool named mythinpool of size 10G under volume group vg1. NOTE: thinpools are special kind of logical volumes carved out of the volume group. Hence in the above example, to create the thinpool mythinpool you must have atleast 10G of freespace in volume group vg1.

Volume Creation

docker volume create command supports the creation of regular lvm volumes, thin volumes, snapshots of regular and thin volumes.

Usage: docker volume create [OPTIONS]

-d, --driver    string    Specify volume driver name (default "local")
--label         list      Set metadata for a volume (default [])
--name          string    Specify volume name
-o, --opt       map       Set driver specific options (default map[])

Following options can be passed using -o or --opt

--opt size
--opt thinpool
--opt snapshot
--opt keyfile

Please see examples below on how to use these options.

Examples

$ docker volume create -d lvm --opt size=0.2G --name foobar

This will create a lvm volume named foobar of size 208 MB (0.2 GB).

docker volume create -d lvm --opt size=0.2G --opt thinpool=mythinpool --name thin_vol

This will create a thinly-provisioned lvm volume named thin_vol in mythinpool.

docker volume create -d lvm --opt snapshot=foobar --opt size=100M --name foobar_snapshot

This will create a snapshot volume of foobar named foobar_snapshot. For thin snapshots, use the same command above but don't specify a size.

docker volume create -d lvm --opt size=0.2G --opt keyfile=/root/key.bin --name crypt_vol

This will create a LUKS encrypted lvm volume named crypt_vol with the contents of /root/key.bin as a binary passphrase. Snapshots of encrypted volumes use the same key file. The key file must be present when the volume is created, and when it is mounted to a container.