Most of the people are confused after seeing guest device names in different strings. As there are different hypervisors exist, it is highly likely that they get confused…
Here is small description on disk device names..
1) XVDA, XVDB..etc : These are disk names of Xen paravirtualized guests.. ( Xen)
2) HDA, HDB…etc : These are disk devices when you use IDE disks inside the guest.. ( Both in Xen and KVM)
3) VDA, VDB ..etc : These are virtio disks used in KVM context..
4) SDA, SDB...etc : These are scsi disks used in guests..
Hope it helps…