@Override
          public void beforeFailoverByCacheClientUpdater(ServerLocation epFailed) {
            try {
              latch.await(TIMEOUT_MILLIS, MILLISECONDS);
            } catch (InterruptedException ie) {
              // expected - test will shut down the cache which will interrupt
              // the CacheClientUpdater thread that invoked this method
              Thread.currentThread().interrupt();
            }
          }
This tests failing of a primary server in a situation where only one of the rest of the servers
is redundant. After every failure, the order, the dispatcher, the interest registration and the
makePrimary calls are verified. The failure detection in these tests could be either through
CCU or cache operation, whichever occurs first
geode-core/src/distributedTest/java/org/apache/geode/internal/cache/tier/sockets/RedundancyLevelPart3DUnitTest.java