podman-cinder-volume-plugin

This Podman volume plugin makes OpenStack Block Storage volumes (aka Cinder volumes) available as Podman volumes.

How to install?

Download binary:

mkdir -p /usr/local/libexec/podman
podman create --name cinder --pull always ghcr.io/nimbolus/podman-cinder-volume-plugin
podman cp cinder:/cinder /usr/local/libexec/podman/cinder
podman rm cinder

Create configuration file and start plugin via systemd:

curl -o /etc/podman-cinder-volume-plugin.env https://raw.githubusercontent.com/nimbolus/podman-cinder-volume-plugin/refs/heads/main/dist/config.env
chmod 0600 /etc/podman-cinder-volume-plugin.env

curl -o /etc/systemd/system/podman-cinder-volume-plugin.service https://raw.githubusercontent.com/nimbolus/podman-cinder-volume-plugin/refs/heads/main/dist/systemd.service
systemctl daemon-reload
systemctl enable --now podman-cinder-volume-plugin.service

Finally, register the plugin in /etc/containers/containers.conf:

[engine]
volume_plugin_timeout = 30

[engine.volume_plugins]
cinder = "/var/run/docker/plugins/cinder.sock"

Supported env vars

Here's the list of env vars supported by this plugin:

Name	Default Value	Description
OS_AUTH_URL		See [1].
OS_USERNAME		See [1].
OS_USERID		See [1].
OS_PASSWORD		See [1].
OS_PASSCODE		See [1].
OS_TENANT_ID		See [1].
OS_TENANT_NAME		See [1].
OS_DOMAIN_ID		See [1].
OS_DOMAIN_NAME		See [1].
OS_APPLICATION_CREDENTIAL_ID		See [1].
OS_APPLICATION_CREDENTIAL_NAME		See [1].
OS_APPLICATION_CREDENTIAL_SECRET		See [1].
OS_PROJECT_ID		See [1].
OS_PROJECT_NAME		See [1].
OS_REGION_NAME		Name of the OpenStack region where Compute & Block Storage resources are located.
DEFAULT_SIZE	20	Default volume size in GB.
VOLUME_PREFIX		Name prefix of volumes managed by this plugin.
LOG_LEVEL	info	Log level (either: trace, debug, info, warn, error, fatal, panic).
DEBUG		Enable /pprof/trace endpoint when the value is not empty.

[1] https://docs.openstack.org/python-openstackclient/pike/cli/man/openstack.html#environment-variables

Supported volume options

Here's the list of options you can pass when creating a volume :

Name	Default Value	Description
size	The value of DEFAULT_SIZE env var	The size of the underlying Block Storage volume.
availability_zone	N/A	AZ where the underlying Block Storage volume should be created.
consistency_group	N/A	See https://docs.openstack.org/cinder/latest/admin/blockstorage-consistency-groups.html
description	N/A	Description of the underlying Block Storage volume.
source_snapshot	N/A	ID of the Block Storage snaphost used to create the volume.
source_backup	N/A	ID of the Block Storage backup used to create the volume.
volume_type	N/A	Block storage volume type.
uid	0	Default UID set on the volume root dir after formatting the volume.
gid	0	Default GID set on the volume root dir after formatting the volume.
mode	0750	Default file mode set on the volume root dir after formatting the volume.

For instance, if you want to define the size of a volume and the source snapshot the volume should be created from, with Docker CLI:

$ podman volume create -d cinder -o size=40 -o source_snapshot=<snapshot-uuid> test

And with docker-compose:

services:
  # ...

volumes:
  test:
    name: test
    driver: cinder
    driver_opts:
      size: 40
      source_snapshot: "<snapshot-uuid>"