No, not support configure it in runtime. But if you want to check the server CA certificate, you could input a trusted CA pem in your MQTT config. When you input a CA pem, it will use the CA pem to check the server when TLS handshake, no matter you enable the config CONFIG_ESP_TLS_SKIP_SERVER_CERT_V...

Sorry that esp_http_client not support set source port. The source port is a random value from 49152 to 65535.

You can keep the mqtt config code and only enable CONFIG_ESP_TLS_SKIP_SERVER_CERT_VERIFY by idf.py menuconfig(Components config->ESP-TLS->[*]Allow potentially insecure options->[*] Skip server ...)

能否提供下 ESP32 侧的日志。

能否提供下你的 sdkconfig 以及打开 mbedtls debug 查看下 mbedtls 握手所使用的套件。

CONFIG_LOG_TIMESTAMP_SOURCE_SYSTEM is disabled as default and will not affect other parts of ESP-IDF. Could you please share more details about the issue when you disable CONFIG_LOG_TIMESTAMP_SOURCE_SYSTEM.

It has the default softap ip 192.168.4.1.

这本书的代码目前不适合使用 IDF 5.0 进行编译，建议使用书中推荐的版本，如果需要使用 IDF 5.0，会有很多编译问题需要解决。

From your log, it seems the max SYN retries reached and peer no response. You need check whether the packet sent out from WIFI, it need capture air packet or route packet.

It seems your log not print any lwip log, you may need clean your build project and re-build. For DNS debug open, you may modify the clode https://github.com/espressif/esp-lwip/b ... pt.h#L3533. Change LWIP_DBG_OFF to LWIP_DBG_ON.