assertEquals(1, nnSnapshotManager.getNumSnapshottableDirs());
// 3. Start up a 2NN and have it do a checkpoint. It will have foo and its
// snapshot in its list of snapshottable dirs referenced from the
// SnapshotManager, as well as in the file system tree.
secondary.doCheckpoint();
assertEquals(1, secondarySnapshotManager.getNumSnapshots());
assertEquals(1, secondarySnapshotManager.getNumSnapshottableDirs());
// 4. Disallow snapshots on and delete foo on the NN. The snapshot count
// will go down to 0 and the snapshottable dir will be removed from the fs