title: Redis Replication: Does slave ever read from snapshot?
body: <p>I have a redis setup with sentinels and multiple slaves, each slave as well as the master writes persistently to a snapshot file. </p>
  
  <p>When I restart the system, every slave has more keys in their instance than the master has (but less keys than are present in their snapshot file), and I do not understand why?</p>
  
  <p>1) My question, does a slave ever read the snapshot file at startup or it only synch with the master? </p>
  
  <p>2) I never copy my snapshot files, does this lead to overwrite problems?</p>
  
  <p>3) If I have keys with EXPIRATION, are those removed form the snapshot file at the corresponding time? </p>