assert caches.get(1).peek(fqnTransformer.getBackupRoot(caches.get(0).getLocalAddress()), false) != null : "Should have new buddy's backup root.";
assert caches.get(1).peek(fqnTransformer.getBackupRoot(cache2Addr), false) == null : "Should not have dead node as a backup root.";
assert caches.get(1).peek(Fqn.fromRelativeElements(fqnTransformer.getDeadBackupRoot(cache2Addr), 1), false) == null : "Should not have dead node as a defunct backup root.";
replListener0.expect(DataGravitationCleanupCommand.class);
// according to data gravitation, a call to *any* cache should retrieve the data, and move the data to the new cache.
assertEquals("Value should have gravitated", value, caches.get(1).get(fqn, key));
replListener0.waitForReplicationToOccur();