diff --git a/src/esx/esx_storage_backend_iscsi.c b/src/esx/esx_storage_backend_iscsi.c
index 96b472ee07..b106c517e8 100644
--- a/src/esx/esx_storage_backend_iscsi.c
+++ b/src/esx/esx_storage_backend_iscsi.c
@@ -220,7 +220,7 @@ esxStoragePoolLookupByUUID(virConnectPtr conn,
          target; target = target->_next) {
         md5_buffer(target->iScsiName, strlen(target->iScsiName), md5);
 
-        if (memcmp(uuid, md5, VIR_UUID_STRING_BUFLEN) == 0)
+        if (memcmp(uuid, md5, VIR_UUID_BUFLEN) == 0)
             break;
     }