Autoreconnect and failing WiFi.begin

[bertmelis]

Board

esp32c3

Device Description

Wemos C3 mini

Hardware Configuration

base board powered by USB

Version

v2.0.9

IDE Name

Platformio

Operating System

Windows 11

Flash frequency

40Mhz

PSRAM enabled

no

Upload speed

115200

Description

On autoreconnecting to WiFi, the code calls WiFi.disconnect() and afterwards WiFi.begin(ssid, psk).

It may happen that the call to begin fails. Apparently, in this case, no callback is fired to signal the failed connection and no further attempt is made to reconnect again.

I do have low memory issues because of TLS connections that are closing/retrying after the WiFi loss. I suppose they are only cleaned up after a while by the framework.

I'm using the 2.x release.

Sketch

Simple state machine in repo here: https://github.com/bertmelis/espMqttManager/blob/main/src/espMqttManager.cpp

Debug Message

[ 50101][V][ssl_client.cpp:369] send_ssl_data(): Writing HTTP request with 45 bytes...
[ 50111][V][ssl_client.cpp:369] send_ssl_data(): Writing HTTP request with 2 bytes...
[ 50117][V][ssl_client.cpp:321] stop_ssl_socket(): Cleaning SSL connection.
[ 50119][I][espMqttManager.cpp:290] onMqttClientDisconnected(): Disconnected from MQTT (CS-1)
[ 50123][I][espMqttManager.cpp:234] reconnectWaitCleanSession(): Reconnecting to MQTT (CS)
[ 50136][V][ssl_client.cpp:62] start_ssl_client(): Free internal heap before TLS 211904
[ 50138][V][ssl_client.cpp:68] start_ssl_client(): Starting socket
[ 50154][V][ssl_client.cpp:146] start_ssl_client(): Seeding the random number generator
[ 50157][V][ssl_client.cpp:155] start_ssl_client(): Setting up the SSL/TLS structure...
[ 50160][V][ssl_client.cpp:178] start_ssl_client(): Loading CA cert
[ 50178][V][ssl_client.cpp:254] start_ssl_client(): Setting hostname for TLS session...
[ 50180][V][ssl_client.cpp:269] start_ssl_client(): Performing the SSL/TLS handshake...
[ 50987][E][ssl_client.cpp:37] _handle_error(): [start_ssl_client():273]: (-17040) RSA - The public key operation failed : BIGNUM - Memory allocation failed
[ 50990][E][WiFiClientSecure.cpp:144] connect(): start_ssl_client: -17040
[ 50997][V][ssl_client.cpp:321] stop_ssl_socket(): Cleaning SSL connection.
[ 51005][V][ssl_client.cpp:321] stop_ssl_socket(): Cleaning SSL connection.
[ 51011][I][espMqttManager.cpp:294] onMqttClientDisconnected(): Disconnected from MQTT (CS-2)
[ 58165][I][espMqttManager.cpp:294] onMqttClientDisconnected(): Disconnected from MQTT (CS-2)
[ 60661][V][WiFiGeneric.cpp:362] _arduino_event_cb(): STA Disconnected: SSID: VHS100-SH, BSSID: a2:21:b7:9f:89:cf, Reason: 200
[ 60661][D][WiFiGeneric.cpp:1035] _eventCallback(): Arduino Event: 5 - STA_DISCONNECTED
[ 60668][W][WiFiGeneric.cpp:1057] _eventCallback(): Reason: 200 - BEACON_TIMEOUT
[ 60676][D][WiFiGeneric.cpp:1077] _eventCallback(): WiFi Reconnect Running
[ 60683][V][WiFiGeneric.cpp:97] set_esp_interface_ip(): Configuring Station static IP: 0.0.0.0, MASK: 0.0.0.0, GW: 0.0.0.0

After this log, the esp stays silent.

### Other Steps to Reproduce

_No response_

### I have checked existing issues, online documentation and the Troubleshooting Guide

- [X] I confirm I have checked existing issues, online documentation and Troubleshooting guide.

[mrengineer7777]

Feature request: Make WiFi.begin() gracefully handle low memory situations.

[bertmelis]

I must admit I solved my low memory issue so I don't suffer this issue anymore. But underlying, the issue remains of course.

WiFi.begin() gracefully handles low memory situations as it returns WL_CONNECT_FAILED. This issue is that afterwards, there is no event anymore to hook into for a next attempt to reconnect.