10.5. Read Only Disks in Red Hat Enterprise Virtualization

Some applications require administrators to share data with read-only rights. You can do this when creating or editing a disk attached to a virtual machine via the Disks tab in the details pane of the virtual machine and selecting the Read Only check box. That way, a single disk can be read by multiple cluster-aware guests, while an administrator maintains writing privileges.

You cannot change the read-only status of a disk while the virtual machine is running.