def post(method, hmc, uri, uri_parms, body, logon_required,
             wait_for_completion):
        """Operation: Mount ISO Image (requires DPM mode)."""
        assert wait_for_completion is True  # synchronous operation
        partition_oid = uri_parms[0]
        partition_uri = '/api/partitions/' + partition_oid
        try:
            partition = hmc.lookup_by_uri(partition_uri)
        except KeyError:
            raise InvalidResourceError(method, uri)
        cpc = partition.manager.parent
        assert cpc.dpm_enabled
        check_valid_cpc_status(method, uri, cpc)
        check_partition_status(method, uri, partition,
                               invalid_statuses=['starting', 'stopping'])

        # Parse and check required query parameters
        query_parms = parse_query_parms(method, uri, uri_parms[1])
        try:
            image_name = query_parms['image-name']
        except KeyError:
            raise BadRequestError(
                method, uri, reason=1,
                message="Missing required URI query parameter 'image-name'")
        try:
            ins_file_name = query_parms['ins-file-name']
        except KeyError:
            raise BadRequestError(
                method, uri, reason=1,
                message="Missing required URI query parameter 'ins-file-name'")

        # Reflect the effect of mounting in the partition properties
        partition.properties['boot-iso-image-name'] = image_name
        partition.properties['boot-iso-ins-file'] = ins_file_name
        return {}