socket接收报文，在阿里云的服务器上只能接收到1024字节长度的报文

问题如题，socket接收报文，在阿里云的服务器上只能接收到1024字节长度的报文，自己本地测试的时候可以接收完整，发布到服务器上就不行。代码如下：
InputStream is=null;
            InputStreamReader isr=null;
            BufferedReader br=null;
            ByteArrayOutputStream bytesOut=null;
            try {
                socket.setReceiveBufferSize(6048);
                logger.info("客户端数据已经连接");
                is=socket.getInputStream();
                isr=new InputStreamReader(is,"GBK");
                br=new BufferedReader(isr);
                bytesOut = new ByteArrayOutputStream();

                byte[] buffer = new byte[1024];
                int count = 0;
                do{
                    count = is.read(buffer);
                    bytesOut.write(buffer,0,count);
                }while (is.available() != 0);
                
                //将接收的请求内容用http请求转发到fre
                String reqData=bytesOut.toString("GBK");
                //String reqData = buffer.toString();
                 logger.info("reqData="+reqData);