The floating disk or shareable disks feature of Red Hat Enterprise Virtualization will allow you to carve out a new virtual disk with the shareable option enabled. Virtual disks marked shareable are independent of any virtual machines and can be attached to a single or multiple numbers of virtual machines. This will be useful in scenarios where an application requires storage to be shared across virtual machines and integrated with high-availability cluster software on those virtual machines to create a group of cluster nodes with shared storage access.

Please be careful while using floating disks. Using shareable disks and mounting the shared disks across multiple virtual machines at the same time (without using any cluster-aware software to coordinate disk read and write of the mounted file system) leads to data corruption. For example, you can use floating disks across two virtual machines and build an active/passive cluster service using Red Hat's high-availability add...