Latest revision as of 04:29, 20 February 2014

Virtio-SCSI

VirtIO SCSI is a new para-virtualized SCSI controller device for KVM instances. It has been designed to replace virtio-blk, increase it's performance and improve scalability. The interface is capable of handling multiple block devices per virtual SCSI adapter, keeps the standard scsi device naming in the guests (e.x /dev/sda) and support SCSI devices passthrough.

Image properties

The SCSI controller model can be set to virtio-scsi by proving the hw_disk_bus_model=virtio-scsi property in Glance image metadata. Otherwise, libvirt will automatically configure it's default model.

glance image-update \
       --property hw_scsi_model=virtio-scsi \
       [image]

Virtual Devices

All virtual devices which has it's bus set to "scsi" will be tied to this controller. Currently the following properties can be set to scsi, together with the hw_scsi_model: hw_cdrom_bus hw_disk_bus hw_floppy_bus

However, no exception will be raise is set without any addition bus properties.