• Glance image services include discovering, registering,
and retrieving virtual machine images. Glance has a
RESTful API that allows querying of VM image metadata
as well as retrieval of the actual image.
• VM images made available through Glance can be stored
in a variety of locations from simple filesystems to object-
storage systems like the OpenStack Swift project.
OpenStack Glance Components
• Accepts Image API calls for image discovery, retrieval, and storage.
• Stores, processes, and retrieves metadata about images. Metadata
includes items such as size and type.
• glance database
• Stores image metadata and you can choose your database
depending on your preference. Most deployments use MySQL or
• Storage repository for image files
OpenStack Glance - Supported Disk and
• Disk Formats
• raw (unstructured)
• qcow2 (Qemu)
• vhd, vmdk, vdi (Hyper-V, Esxi, Virtual Box)
• aki, ari, ami (amazon images)
• Container Formats
• aki, ari, ami
OpenStack Glance Image Cache
• By default, image caching is disabled.
• The Glance API server may be configured to have an
optional local image cache. A local image cache stores a
copy of image files, essentially enabling multiple API
servers to serve the same image file, resulting in an
increase in scalability due to an increased number of
endpoints serving an image file.
OpenStack Glance Storage Backend
• There are a number of configuration options in Glance
that control how Glance stores disk images.
• glance-api.conf config file
• Available options for this option are (file, swift, s3, rbd,
sheepdog, cinder or vsphere).
OpenStack Glance Kilo Release
• Ability to deactivate an image.
• Basic support for Image conversion during the import
process of an Image
• Images v2 API supports new sorting syntax including
ability to specify the sort dir for each key.
• Multiple datastore support for VMware Storage driver.
• Glance Swift Store to use Multiple Containers for Storing