public void init() throws ReplicationException {
    // Loading all existing peerIds into peer cache.
    for (String peerId : this.peerStorage.listPeerIds()) {
      addPeer(peerId);
    }
  }
This provides an class for maintaining a set of peer clusters. These peers are remote slave
clusters that data is replicated to.
<p>
We implement {@link ConfigurationObserver} mainly for recreating the
{@link ReplicationPeerStorage}, so we can change the {@link ReplicationPeerStorage} without
restarting the region server.
hbase-replication/src/main/java/org/apache/hadoop/hbase/replication/ReplicationPeers.java