2.3. Storage Domain Types

The Data Domain stores the hard disk images of all virtual machines in the Red Hat Virtualization environment. Disk images may contain an installed operating system or data stored or generated by a virtual machine. Data storage domains support NFS, iSCSI, FCP, GlusterFS and POSIX compliant storage. A data domain cannot be shared between multiple data centers.

The Export Domain provides transitory storage for hard disk images and virtual machine templates being transferred between data centers. Additionally, export storage domains store backed up copies of virtual machines. Export storage domains support NFS storage. Multiple data centers can access a single export storage domain but only one data center can use it at a time.

The ISO Domain stores ISO files, also called images. ISO files are representations of physical CDs or DVDs. In the Red Hat Virtualization environment the common types of ISO files are operating system installation disks, application installation disks, and guest agent installation disks. These images can be attached to virtual machines and booted in the same way that physical disks are inserted into a disk drive and booted. ISO storage domains allow all hosts within the data center to share ISOs, eliminating the need for physical optical media.