@Override
  public boolean isPeerEnabled(String peerId) throws ReplicationException {
    try {
      return Arrays.equals(ENABLED_ZNODE_BYTES,
        ZKUtil.getData(zookeeper, getPeerStateNode(peerId)));
    } catch (KeeperException | InterruptedException e) {
      throw new ReplicationException("Unable to get status of the peer with id=" + 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