Hello Quectel Support Team,
We are currently integrating an EC200U-CN modem with AWS IoT Core using MQTT over TLS 1.2 with mutual TLS authentication.
We are blocked by a persistent TLS handshake failure and need urgent technical assistance.
We previously raised a related issue here:
Previous Quectel thread – EC200U-CN AWS IoT TLS handshake failed
Unfortunately, we have not received a response from the Quectel team even after updating the thread.
Module Information
- Module: EC200U-CN
- Firmware:
EC200UCNAAR03A17M08 - Application: AWS IoT Core
- Protocol: MQTT
- MQTT Port: 8883
- TLS: TLS 1.2
- Authentication: AWS IoT X.509 mutual TLS
EC200U-CN AWS IoT TLS Handshake Failed - Error 579 / QMTOPEN 0,5 - A13M08
Hi Quectel Support, Thank you for providing the latest USB driver. I was able to install the driver, enter the firmware download mode, and successfully upgrade the EC200U-CN firmware. Firmware s…
Network connectivity is working
The modem successfully:
- Registers on LTE network
- Activates PDP context
- Obtains an IP address
- Resolves the AWS IoT endpoint
- Successfully reaches the AWS endpoint using
AT+QPING
Example:
AT+QIACT?+QIACT: 1,1,1,"10.112.213.56"OK
AWS endpoint:
a7t6qe56nuogw-ats.iot.ap-south-1.amazonaws.com
Therefore, this does not appear to be an APN, PDP, DNS, or basic network connectivity problem.
TLS Configuration
We uploaded the following certificates successfully to UFS:
AmazonRootCA1.pemdeviceCert.pemprivateKey.pem
The modem reports the expected file sizes:
AmazonRootCA1.pem = 1188 bytesdeviceCert.pem = 1220 bytesprivateKey.pem = 1679 bytes
TLS configuration:
AT+QSSLCFG="cacert",2,"UFS:AmazonRootCA1.pem"OK
AT+QSSLCFG="clientcert",2,"UFS:deviceCert.pem"OK
AT+QSSLCFG="clientkey",2,"UFS:privateKey.pem"OK
AT+QSSLCFG="seclevel",2,2OK
AT+QSSLCFG="sslversion",2,3OK
AT+QSSLCFG="ciphersuite",2,0xFFFFOK
AT+QSSLCFG="sni",2,1OK
AT+QSSLCFG="ignorelocaltime",2,1OK
All configuration commands return OK.
Actual TLS Failure
The important point is that we tested TLS directly using QSSLOPEN, without MQTT.
Command:
AT+QSSLOPEN=1,2,0,"a7t6qe56nuogw-ats.iot.ap-south-1.amazonaws.com",8883,0
Result:
+QSSLOPEN: 0,579
Then:
AT+QIGETERROR
returns:
+QIGETERROR: 579,ssl handshake failed
Therefore, the failure occurs during the TLS handshake itself, before MQTT connection establishment.
When using MQTT, we consequently receive:
+QMTOPEN: 0,5
Manual AT Command Testing Also Failed
We also performed the connection manually using AT commands rather than our application firmware.
The same TLS handshake failure occurs.
Therefore, this does not appear to be caused by our application MQTT implementation.
We have also tried:
- TLS 1.2
- SNI enabled
seclevel=2ciphersuite=0xFFFF- Correct CA certificate
- Correct client certificate
- Correct private key
- Manual
QSSLOPEN - MQTT
QMTOPEN
But the TLS handshake still fails with:
579 - ssl handshake failed
Could the Quectel technical team please investigate the following urgently?
1. Is error 579 a known TLS/firmware issue on:
EC200UCNAAR03A17M08
2. Is there a known firmware bug/interoperability issue with AWS IoT Core?
3. Is A17M08 the recommended/latest firmware for AWS IoT TLS connections?
4. Is there a newer firmware version that fixes TLS handshake error 579?
If yes, please provide the exact firmware version/download package recommended for EC200U-CN.
5. Please confirm the correct QSSLCFG configuration for AWS IoT Core.
In particular:
seclevelsslversionciphersuitesniignorelocaltime
6. Please explain what specifically causes:
+QSSLOPEN: 0,579+QIGETERROR: 579,ssl handshake failed
on EC200U-CN.
This Is Blocking Our Product Development
We have already spent significant time validating the network connection, certificates, MQTT configuration, and manual AT-command sequence.
The modem can establish cellular connectivity and reach the AWS endpoint, but the TLS handshake consistently fails.
We therefore need Quectel engineering support rather than further generic MQTT troubleshooting.
Please escalate this case to the EC200U-CN firmware/TLS engineering team and provide a concrete resolution or recommended firmware as soon as possible.
This issue is currently blocking our AWS IoT integration and product development.
Attached Full AT command logs for your reference need immediate response from support team
Thank you.
EC200U_A17M08_AWS_IoT_TLS_Handshake_Failure_AT_Logs.zip (1.8 KB)
EC200U_A17M08_AWS_IoT_TLS_Handshake_Failure_Manual_AT_Logs.zip (1.1 KB)