assertEquals(NUM_MASTERS, masterThreads.size());
// attempt to stop one of the inactive masters
LOG.debug("\n\nStopping a backup master\n");
int backupIndex = (activeIndex == 0 ? 1 : activeIndex - 1);
cluster.stopMaster(backupIndex, false);
cluster.waitOnMaster(backupIndex);
// verify still one active master and it's the same
for (int i = 0; i < masterThreads.size(); i++) {
if (masterThreads.get(i).getMaster().isActiveMaster()) {