Using some RTOS built-in mbedTLS to connect to AWS IoT Core might fail due to MBEDTLS_ERR_SSL_INVALID_RECORD(-0x7200 or -29184) during ssl handshake. There are several possible causes:

  • The task stack set for mbedTLS running is not enough. Increase task stack and try again.
  • MBEDTLS_SSL_MAX_CONTENT_LEN is not enough. Increase MBEDTLS_SSL_MAX_CONTENT_LEN to 16384 and try again.