Websocket RFC JCo Failure

[kennych]

Transferring binary over 1.5MB seeing failures in websocket RFC. Works fine for under 1.5mb.

Also see random request sporadically fail.

Caused by: com.sap.conn.rfc.exceptions.RfcIoException: read: Reading from InputStream failed: java.util.concurrent.ExecutionException: java.util.concurrent.ExecutionException: javax.net.ssl.SSLProtocolException: Input record too big: max = 16709 len = 48988

2023-06-14 18:55:28,323 ERROR [JCoServerThread-2] jco.JcoHelper (JcoHelper.java:699) - Exception in server com.sap.conn.jco.rt.WebSocketServer@680d4a6awith connection id = 2-W|8212with context = com.sap.conn.jco.rt.AbstractServerWorker$ServerContext@6f2fc81

com.sap.conn.jco.JCoException: initial read of parameter not successful

at com.sap.conn.jco.rt.AbstractConnection.generateJCoException(AbstractConnection.java:623) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.jco.rt.AbstractServerConnection.listen(AbstractServerConnection.java:1036) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.jco.rt.WebSocketServerWorker.handleReadEvent(WebSocketServerWorker.java:94) [sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.jco.rt.WebSocketServerWorker.dispatch(WebSocketServerWorker.java:47) [sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.jco.rt.AbstractServerWorker.loop(AbstractServerWorker.java:357) [sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.jco.rt.AbstractServerWorker.run(AbstractServerWorker.java:323) [sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at java.lang.Thread.run(Thread.java:833) [?:?]

Caused by: com.sap.conn.rfc.exceptions.RfcException: initial read of parameter not successful

at com.sap.conn.rfc.engine.RfcIoOpenCntl.RfcGetData(RfcIoOpenCntl.java:2492) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.jco.rt.AbstractServerConnection.dispatchRequest(AbstractServerConnection.java:1956) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.jco.rt.AbstractServerConnection.listen(AbstractServerConnection.java:990) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

... 5 more

Caused by: com.sap.conn.rfc.exceptions.RfcGetException: initial read of parameter not successful

at com.sap.conn.rfc.engine.cbrfc.receiveStream.CbRfcReceiveStream.initialize(CbRfcReceiveStream.java:48) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.rfc.engine.cbrfc.decompress.CbRfcZLibDecompression.initialize(CbRfcZLibDecompression.java:31) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.rfc.engine.cbrfc.decompress.CbRfcDecompressionReader.initialize(CbRfcDecompressionReader.java:38) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.rfc.engine.cbrfc.deserialize.CbRfcDeserializer.cbRfcDeserializeParams(CbRfcDeserializer.java:99) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.rfc.engine.RfcImp.receiveCbRfcSerializedData(RfcImp.java:442) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.rfc.engine.RfcGet.ab_rfcget(RfcGet.java:440) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.rfc.engine.RfcRcv.ab_rfcreceive(RfcRcv.java:41) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.rfc.engine.RfcIoOpenCntl.RfcGetData(RfcIoOpenCntl.java:2479) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.jco.rt.AbstractServerConnection.dispatchRequest(AbstractServerConnection.java:1956) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.jco.rt.AbstractServerConnection.listen(AbstractServerConnection.java:990) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

... 5 more

Caused by: com.sap.conn.rfc.exceptions.RfcIoException: read: Reading from InputStream failed: java.util.concurrent.ExecutionException: java.util.concurrent.ExecutionException: javax.net.ssl.SSLProtocolException: Input record too big: max = 16709 len = 48988

at com.sap.conn.rfc.engine.RfcIoOpenCntl.ab_rfcread(RfcIoOpenCntl.java:847) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.rfc.engine.cbrfc.receiveStream.CbRfcReceiveStream.initialize(CbRfcReceiveStream.java:44) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.rfc.engine.cbrfc.decompress.CbRfcZLibDecompression.initialize(CbRfcZLibDecompression.java:31) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.rfc.engine.cbrfc.decompress.CbRfcDecompressionReader.initialize(CbRfcDecompressionReader.java:38) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.rfc.engine.cbrfc.deserialize.CbRfcDeserializer.cbRfcDeserializeParams(CbRfcDeserializer.java:99) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.rfc.engine.RfcImp.receiveCbRfcSerializedData(RfcImp.java:442) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.rfc.engine.RfcGet.ab_rfcget(RfcGet.java:440) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.rfc.engine.RfcRcv.ab_rfcreceive(RfcRcv.java:41) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.rfc.engine.RfcIoOpenCntl.RfcGetData(RfcIoOpenCntl.java:2479) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.jco.rt.AbstractServerConnection.dispatchRequest(AbstractServerConnection.java:1956) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

at com.sap.conn.jco.rt.AbstractServerConnection.listen(AbstractServerConnection.java:990) ~[sapjco3.jar:20221214 2042 [3.1.7 (2022-12-14)]]

... 5 more

[MarkusTolksdorf]

Hello Kenny,

this is not a topic that is supposed to be discussed in answers.sap.com. It will require a deeper analysis and traces and is actually a support case. Please open a customer ticket for it on BC-MID-CON-JCO.

Best regards
Markus

[kennych]

Ok i will but it seems like a bug. Its TLS frsgment seem to go against tls spec hence the error. I also verified its not related to binary size in the jco table....random binary work and random fail.