@Test
  public void testDiskDirs() throws Exception {
    File f1 = new File("testDiskDir1");
    f1.mkdir();
    File f2 = new File("testDiskDir2");
    f2.mkdir();
    try {
      AttributesFactory af = new AttributesFactory();
      af.setDiskDirs(new File[] {f1, f2});
      af.setDataPolicy(DataPolicy.PERSISTENT_REPLICATE);
      Region r = cache.createRegion("r", af.create());
      {
        LocalRegion lr = (LocalRegion) r;
        DiskStoreImpl ds = lr.getDiskStore();
        File[] dirs = ds.getDiskDirs();
        assertEquals(2, dirs.length);
        assertEquals(f1, dirs[0]);
        assertEquals(f2, dirs[1]);
      }
      r.localDestroyRegion();

      // now try it with a pr
      af.setDataPolicy(DataPolicy.PERSISTENT_PARTITION);
      r = cache.createRegion("r", af.create());
      {
        LocalRegion lr = (LocalRegion) r;
        DiskStoreImpl ds = lr.getDiskStore();
        File[] dirs = ds.getDiskDirs();
        assertEquals(2, dirs.length);
        assertEquals(f1, dirs[0]);
        assertEquals(f2, dirs[1]);
      }
      r.put("key", "value");
      {
        PartitionedRegion pr = (PartitionedRegion) r;
        PartitionedRegionDataStore prds = pr.getDataStore();
        Set<BucketRegion> s = prds.getAllLocalBucketRegions();
        assertTrue(s.size() > 0);
        for (BucketRegion br : s) {
          LocalRegion lr = br;
          DiskStoreImpl ds = lr.getDiskStore();
          File[] dirs = ds.getDiskDirs();
          assertEquals(2, dirs.length);
          assertEquals(f1, dirs[0]);
          assertEquals(f2, dirs[1]);
        }
      }
      r.localDestroyRegion();
    } finally {
      cache.close();
      removeDir(f1);
      removeDir(f2);
    }
  }
Make sure the old diskDirs apis get mapped onto the diskStore.
geode-core/src/integrationTest/java/org/apache/geode/internal/cache/DiskOldAPIsJUnitTest.java