When using MC60 MQTT connecting with AWS Iot Core server, we are facing issue that after successful connection, and periodic publishing (every 10 seconds), the module sends MQTT Link layer error “+QMTSTAT: 0,1”. I have checked the AWS Iot log, and the disconnection is not initiated by the server.
What could be the problem?
[2023/04/09 23:15:47] ← RIL is ready →
[2023/04/09 23:15:48] OnURCHandler:
+CREG: 2
[2023/04/09 23:15:48] OnURCHandler:
+CGREG: 0
[2023/04/09 23:15:48] OnURCHandler:
+CFUN: 1
[2023/04/09 23:15:48] OnURCHandler:
+CPIN: READY
[2023/04/09 23:15:48] OnURCHandler:
+CGREG: 2
[2023/04/09 23:15:50] OnURCHandler:
+QBTVISB: 1
[2023/04/09 23:15:50] ← GSM network status:2 →
[2023/04/09 23:15:50] ← GPRS network status:0 →
[2023/04/09 23:15:50] ← SIM card is ready →
[2023/04/09 23:15:50] ← GPRS network status:2 →
Call Ready
[2023/04/09 23:15:51] ← Sys Init Status 2 →
SMS Ready
[2023/04/09 23:15:52] ← Sys Init Status 3 →
[2023/04/09 23:15:52] ← Application can program SMS →
[2023/04/09 23:15:54] OnURCHandler:
+CREG: 1
[2023/04/09 23:15:54] ← Module has registered to GSM network →
[2023/04/09 23:15:54] MQTTClient _OnURCNotification: msg=4098 param1=3 param2=1
[2023/04/09 23:15:54] OnURCNotification Other URC: type=3
[2023/04/09 23:15:54] OnURCHandler:
OK
[2023/04/09 23:16:00] OnURCHandler:
+CGREG: 1
+CREG: 1,1
+CGREG: 1,1
[2023/04/09 23:16:26] //<register recv callback,ret = 0
[2023/04/09 23:16:26] //<Set PDP context 0
[2023/04/09 23:16:26] //<Setiing APN M2MISAFE
[2023/04/09 23:16:26] //<Set APN M2MISAFE
[2023/04/09 23:16:27] //<Activate PDP context,ret = 0 errCode=0
[2023/04/09 23:16:27] ← Send AT:AT+QMTCFG=“SSL”,0,1,2, ret = 0 →
[2023/04/09 23:16:27] ← Send AT:AT+QMTCFG=“KEEPALIVE”,0,120, ret = 0 →
[2023/04/09 23:16:27] ← Send AT:AT+QSSLCFG=“ignorertctime”,1, ret = 0 →
[2023/04/09 23:16:27] ← Send AT:AT+QSSLCFG=“sslversion”,2,4, ret = 0 →
[2023/04/09 23:16:27] ← Send AT:AT+QSSLCFG=“ciphersuite”,2,“0xFFFF”, ret = 0 →
[2023/04/09 23:16:27] ← Send AT:AT+QSSLCFG=“seclevel”,2,2, ret = 0 →
[2023/04/09 23:16:27] ← Send AT:AT+QSSLCFG=“cacert”,2,“RAM:CA0”, ret = 0 →
[2023/04/09 23:16:27] ← Send AT:AT+QSSLCFG=“clientcert”,2,“RAM:CC0”, ret = 0 →
[2023/04/09 23:16:27] ← Send AT:AT+QSSLCFG=“clientkey”,2,“RAM:CK0”, ret = 0 →
[2023/04/09 23:16:27] ← Set SSL, ret=0 →
[2023/04/09 23:16:27] ← ATResponse_SSL_handler_CERTIFICATE_WRITE line:
CONNECT
, len = 11 →
[2023/04/09 23:16:27] ← ATResponse_SSL_handler_CERTIFICATE_WRITE line:
+QSECWRITE: 1188,2d13
, len = 25 →
[2023/04/09 23:16:27] ← ATResponse_SSL_handler_CERTIFICATE_WRITE line:
OK
, len = 6 →
[2023/04/09 23:16:27] ← Send AT:AT+QSECWRITE=“RAM:CA0”,1188,100, ret = 0 Ql_strlen=1188 pCertInfo->uCACertLen=1188–>
[2023/04/09 23:16:27] ← ATResponse_SSL_handler_CERTIFICATE_WRITE line:
CONNECT
, len = 11 →
[2023/04/09 23:16:27] ← ATResponse_SSL_handler_CERTIFICATE_WRITE line:
+QSECWRITE: 1220,b7f
, len = 24 →
[2023/04/09 23:16:27] ← ATResponse_SSL_handler_CERTIFICATE_WRITE line:
OK
, len = 6 →
[2023/04/09 23:16:27] ← Send AT:AT+QSECWRITE=“RAM:CC0”,1220,100, ret = 0 Ql_strlen=1220 pCertInfo->uClientCertLen=1220–>
[2023/04/09 23:16:27] ← ATResponse_SSL_handler_CERTIFICATE_WRITE line:
CONNECT
, len = 11 →
[2023/04/09 23:16:28] ← ATResponse_SSL_handler_CERTIFICATE_WRITE line:
+QSECWRITE: 1679,6c0a
, len = 25 →
[2023/04/09 23:16:28] ← ATResponse_SSL_handler_CERTIFICATE_WRITE line:
OK
, len = 6 →
[2023/04/09 23:16:28] ← Send AT:AT+QSECWRITE=“RAM:CK0”,1679,100, ret = 0 Ql_strlen=1679 pCertInfo->uClientKeyLen=1679 →
[2023/04/09 23:16:28] ← Set SSL CERTIFICATE, ret=0 →
[2023/04/09 23:16:28] [ATResponse_Handler]
OK
[2023/04/09 23:16:28] <–Send AT:AT+QMTCFG=“TIMEOUT”,0,10,0,1, ret = 0 →
[2023/04/09 23:16:28] MQTTClient_Configure timeout success
[2023/04/09 23:16:28] [ATResponse_Handler]
OK
[2023/04/09 23:16:28] <–Send AT:AT+QMTCFG=“SHOWRECVLEN”,0,1, ret = 0 →
[2023/04/09 23:16:28] [ATResponse_Handler]
OK
[2023/04/09 23:16:28] <–Send AT:AT+QMTCFG=“VERSION”,0,1, ret = 0 →
[2023/04/09 23:16:28] MQTTClient_Configure Select version 3.1.1 successfully
[2023/04/09 23:16:28] [ATResponse_Handler]
OK
[2023/04/09 23:16:28] <–Send AT:AT+QMTOPEN=0,“xxxxxxxxxxxx-ats.iot.ap-south-1.amazonaws.com”,8883, ret = 0 →
+QMTOPEN: 0,0
[2023/04/09 23:16:41] Open a MQTT client successfully
[2023/04/09 23:16:41] [ATResponse_Handler]
OK
[2023/04/09 23:16:41] <–Send AT:AT+QMTCONN=0,“hw-7063065305”,“”,“”, ret = 0 →
[2023/04/09 23:16:41] MQTTClient_Connect connect to MQTT server
[2023/04/09 23:16:41] OnURCHandler:
+QMTCONN: 0,0,0
023/04/09 23:16:41] Connect to MQTT server successfully
+QMTSUB: 0,1,0,1,1,1,1,1
+QMTPUB: 0,1,0
[2023/04/09 23:16:52] OnURCHandler:
+QMTPUB: 0,2,0
[2023/04/09 23:17:01] OnURCHandler:
+QMTPUB: 0,3,0
[2023/04/09 23:17:11] OnURCHandler:
+QMTPUB: 0,4,0
[2023/04/09 23:17:21] OnURCHandler:
+QMTPUB: 0,5,0
[2023/04/09 23:17:31] OnURCHandler:
+QMTPUB: 0,6,0
[2023/04/09 23:17:41] OnURCHandler:
+QMTPUB: 0,7,0
[2023/04/09 23:17:52] OnURCHandler:
+QMTPUB: 0,8,0
[2023/04/09 23:18:02] OnURCHandler:
+QMTSTAT: 0,1
[2023/04/09 23:18:02] ← URCMessage: msg=4098 param1=16 param2=-264429532–>
[2023/04/09 23:18:02] MQTT state change: state=1
[2023/04/09 23:18:02] Resetting module as Connection is closed or reset by peer!!