Nova can use Glance service to manage Operating System images that it needs for bringing up instances. Glance can use several types of storage backends such as filestore, s3 etc.
sudo apt-get install -y glance
The default config file at /etc/glance/glance.conf is good to use for a simple file store as the storage backend. Glance can be configured to use other storage backends such as Swift.
Glance uses sqlite as the default database backend. While sqlite offers a quick and easy way to get started, for production use, you may consider a database such as MySQL or PostgreSQL.
Glance has two components - glance-api and glance-registry. These can be controlled using the concerned upstart jobs.
