// clear the list of snapshottable dirs referenced from the
// SnapshotManager. When it writes out an fsimage, the 2NN will write out
// 0 for the snapshot count, but still serialize the snapshottable dir
// referenced in the SnapshotManager even though it no longer appears in
// the file system tree. The NN will not be able to start up with this.
secondary.doCheckpoint();
assertEquals(0, secondarySnapshotManager.getNumSnapshots());
assertEquals(0, secondarySnapshotManager.getNumSnapshottableDirs());
} finally {
if (cluster != null) {
cluster.shutdown();