ClickHouse/tests/integration/test_tmp_policy/configs/config.d/storage_configuration.xml

<yandex>
    <storage_configuration>
        <disks>
            <disk1>
                <path>/disk1/</path>
            </disk1>
            <disk2>
                <path>/disk2/</path>
            </disk2>
        </disks>

        <policies>
            <tmp>
                <volumes>
                    <main>
                        <disk>disk1</disk>
                        <disk>disk2</disk>
                    </main>
                </volumes>
            </tmp>
        </policies>
    </storage_configuration>

    <tmp_policy>tmp</tmp_policy>
</yandex>