diff --git a/src/vz/vz_sdk.c b/src/vz/vz_sdk.c
index 4cd988a8bc37a5faab6dfa5c74621c0385c00fee..e968fdee27f2495ec35b3aba9ef2cf215aaab064 100644
--- a/src/vz/vz_sdk.c
+++ b/src/vz/vz_sdk.c
@@ -563,6 +563,7 @@ prlsdkGetDiskId(PRL_HANDLE disk, int *bus, char **dst)
         *dst = virIndexToDiskName(pos, "hd");
         break;
     case PMS_SCSI_DEVICE:
+    case PMS_UNKNOWN_DEVICE:
         *bus = VIR_DOMAIN_DISK_BUS_SCSI;
         *dst = virIndexToDiskName(pos, "sd");
         break;