@Test
  public void testInvalidArchiveDiskSpaceLimit() {
    Properties props = new Properties();
    props.put(ARCHIVE_DISK_SPACE_LIMIT, "blah");
    assertThatThrownBy(() -> createSystem(props)).isInstanceOf(IllegalArgumentException.class);
  }
Tests that getting the log level is what we expect.
geode-core/src/integrationTest/java/org/apache/geode/distributed/internal/InternalDistributedSystemIntegrationTest.java