void deleteInterface(final String foreignId, final String ipAddress) {
   LOG.debug(
       "deleteInterface: Deleting interface {} from node {}/{}",
       ipAddress,
       getForeignSource(),
       foreignId);
   final Requisition req = getActiveRequisition(false);
   if (req != null) {
     final RequisitionNode node = req.getNode(foreignId);
     if (node != null) {
       req.updateDateStamp();
       node.deleteInterface(ipAddress);
       save(req);
     }
   }
 }