@Override
  public void updatePeerConfig(String peerId, ReplicationPeerConfig peerConfig)
    throws ReplicationException {
    try {
      ZKUtil.setData(this.zookeeper, getPeerNode(peerId),
        ReplicationPeerConfigUtil.toByteArray(peerConfig));
    } catch (KeeperException e) {
      throw new ReplicationException(
        "There was a problem trying to save changes to the " + "replication peer " + peerId, e);
    }
  }
The name of the znode that contains a list of all remote slave (i.e. peer) clusters.
hbase-replication/src/main/java/org/apache/hadoop/hbase/replication/ZKReplicationPeerStorage.java