/* send request to the proxy */
CopyBlockHeader copyBlockHeader = new CopyBlockHeader(
DataTransferProtocol.DATA_TRANSFER_VERSION, namespaceId,
block.getBlockId(), block.getGenerationStamp());
copyBlockHeader.writeVersionAndOpCode(proxyOut);
copyBlockHeader.write(proxyOut);
proxyOut.flush();
// receive the response from the proxy
proxyReply = new DataInputStream(new BufferedInputStream(