@Override
  protected void deserializeStateData(ProcedureStateSerializer serializer) throws IOException {
    super.deserializeStateData(serializer);
    UpdatePeerConfigStateData data = serializer.deserialize(UpdatePeerConfigStateData.class);
    peerConfig = ReplicationPeerConfigUtil.convert(data.getPeerConfig());
    if (data.hasOldPeerConfig()) {
      oldPeerConfig = ReplicationPeerConfigUtil.convert(data.getOldPeerConfig());
    } else {
      oldPeerConfig = null;
    }
    enabled = data.getEnabled();
  }
The procedure for updating the config for a replication peer.
hbase-server/src/main/java/org/apache/hadoop/hbase/master/replication/UpdatePeerConfigProcedure.java