When a client is connected to follower and get disconnected and connects to a leader it gets SESSION MOVED excpetion. This is beacuse of a bug in the new feature of
ZOOKEEPER-417 that we added in 3.2. All the releases before 3.2 DO NOT have this problem. The fix is to make sure the ownership of a connection gets changed when a session moves from follower to the leader. The workaround to it in 3.2.0 would be to swithc off connection from clients to the leader. take a look at leaderServers java property in http://hadoop.apache.org/zookeeper/docs/r3.2.0/zookeeperAdmin.html.