The Nimble BLE_Paired_Device_Info NOT stored in NVS, and forgotton after every reboot.

[Rob58329]

Board

ESP32C3 or ESP32S3

Device Description

Board only

Hardware Configuration

Board only

Version

latest stable Release (if not listed below)

Type

Bug

IDE Name

Arduino IDE v1.8.19 with github.com/espressif/arduino-esp32 as at 14Sep25

Operating System

Windows 10

Flash frequency

80MHz

PSRAM enabled

no

Upload speed

115200

Description

The Nimble BLE_Paired_Device_Info NOT stored in NVS, and forgotton after every reboot.
This failure to save occurrs on both the ESP32C3 and ESP32S3, so probably on all ESP32-NimBLE devices

The below sketch allows this issue to be tested.

Test-A: pair-your-phone to the ESP32C3/ESP32S3, check its paired by pressing 'd'. Then reboot the ESP32S3, and press 'd' again (or try to re-connect your phone).

Test-B: pair-your-phone to the ESP32C3/ESP32S3, check its paired by pressing 'd'. Then delete NVS by pressing 'z'. Then check 'd' again. (or dis/re-connect your phone)

Sketch

// BLE NimBLE: The Nimble BLE_Paired_Device_Info NOT stored in NVS, and forgotton after every reboot.
// This failure to save occurrs on both the ESP32C3 and  ESP32S3, so probably on all ESP32-NimBLE devices

// Test-A: pair-your-phone to the ESP32C3/ESP32S3, check its paired by pressing 'd'. Then reboot the ESP32S3, and press 'd' again (or try to re-connect your phone).
// Test-B: pair-your-phone to the ESP32C3/ESP32S3, check its paired by pressing 'd'. Then delete NVS by pressing 'z'.  Then check 'd' again. (or dis/re-connect your phone)

#if !defined(CONFIG_NIMBLE_ENABLED)
  #error "This code only works using NimBLE"
#endif

#define BLE_NAME "Secure BLE Server"
#define SERVER_PIN 123456

boolean BLE_running=0;

#include "BLEDevice.h"
#include "BLEServer.h"
BLEServer *pServer=nullptr;

class MyServerCallbacks : public BLEServerCallbacks {
  void onConnect(BLEServer *pServer)    {Serial.printf("Device connected (ID=%u)\n",pServer->getConnId()); delay(2);}
  void onDisconnect(BLEServer *pServer) {Serial.println("Device Disconnected"); delay(2);}
};

class MySecurityCallbacks : public BLESecurityCallbacks {
    void onPassKeyNotify(uint32_t pass_key) {Serial.println("Requested PassKey from Client");}
    void onAuthenticationComplete(ble_gap_conn_desc *desc ) {
      boolean BLE_security=desc->sec_state.bonded;
      Serial.printf("&&&&& Authentication %s &&&&&\n", BLE_security ? "OK" : "FAIL"); delay(2);
      if((!BLE_security) and (pServer)) pServer->disconnect(pServer->getConnId());
    }
};

void setup() {
  Serial.begin(115200); delay(2999);
  Serial.printf("ESP_ARDUINO=v%s+\n",ESP_ARDUINO_VERSION_STR); // ESP_ARDUINO=v3.3.0+
  Serial.print("Using BLE stack: "); Serial.println(BLEDevice::getBLEStackString());
  BLE_server_start(BLE_NAME);
  Serial.printf("Now you can Connect from your phone (pw=%u)\n",SERVER_PIN);
  Serial.println("[Serial Commands: d=Display Bonds, e=Erase All-Bonds, z=reset_NVS]"); 
}


void loop() { 
  while (Serial.available()) {
    char c=Serial.read();
    if (c>=32) Serial.write(c);
    else if (c==10) {}
    else Serial.println();
    #if defined(CONFIG_BLUEDROID_ENABLED)
      #error "Use Nimble fot this issue"
    #else
      if (c=='d') {Serial.print("->"); Serial.printf("getNumBonds=%i\n", getNumBonds());}
      if (c=='e') {Serial.println("->deleteAllBonds"); deleteAllBonds();}
      if (c=='z') {Serial.print("->"); reset_NVS();}
   #endif
  }
  delay(100);
}

uint32_t BLE_passkey=SERVER_PIN;
void BLE_server_start(const char* BLE_name) { 
  if (BLE_running) Serial.println("Already Running");
  else {
    BLE_running=true;
    Serial.println("Starting BLE");
    BLEDevice::init(BLE_name); delay(50);
    MySecurityCallbacks *mySecurityCallbacks = new MySecurityCallbacks();
    BLEDevice::setSecurityCallbacks(mySecurityCallbacks);
    BLESecurity *pSecurity = new BLESecurity();
    pSecurity->setCapability(ESP_IO_CAP_OUT);
    pSecurity->setPassKey(true, BLE_passkey);
    pSecurity->setAuthenticationMode(true, true, true);
    pServer = BLEDevice::createServer(); 
    pServer->advertiseOnDisconnect(true);
    BLEServerCallbacks *myServCallbacks=new MyServerCallbacks();
    pServer->setCallbacks(myServCallbacks);
    BLEAdvertising *pAdvertising = BLEDevice::getAdvertising();
    pAdvertising->setScanResponse(true);
    pAdvertising->setMinPreferred(0x06);  // functions that help with iPhone connections issue
    pAdvertising->setMaxPreferred(0x12);
    BLEDevice::startAdvertising();   
  }
}

#include <nvs_flash.h>
void reset_NVS() {
  Serial.println("Clearing NVS pairing data (but does NOT currently clear THESE bonds)...");
  nvs_flash_erase();
  nvs_flash_init();
}

int getNumBonds() {
  int num_peers=-1;
  if (BLE_running) {
    ble_addr_t peer_id_addrs[MYNEWT_VAL(BLE_STORE_MAX_BONDS)];
    int rc = ble_store_util_bonded_peers(&peer_id_addrs[0], &num_peers, MYNEWT_VAL(BLE_STORE_MAX_BONDS)); // NOT using ble_store_util_peer_set!
    if (rc) num_peers=-1; // an error has occured
  } else Serial.println("Err: BLE not running");
  return num_peers;
}

bool deleteAllBonds() {
  int rc=-1;
  if (BLE_running) {
    int rc = ble_store_clear();
    if (rc) Serial.printf("Failed to delete all bonds: rc=%i\n", rc);
    else    Serial.println("All bonds deleted");
  } else Serial.println("Err: BLE not running");
  return (!rc);
}

Debug Message

ESP_ARDUINO=v3.3.0+
Using BLE stack: NimBLE
Starting BLE
Now you can Connect from your phone (pw=123456)
[Serial Commands: d=Display Bonds, e=Erase All-Bonds, z=reset_NVS]
Device connected (ID=1)
Requested PassKey from Client
&&&&& Authentication OK &&&&&
d->getNumBonds=1

z->Clearing NVS pairing data (but does NOT currently clear THESE bonds)...

d->getNumBonds=1

// Rebooted Board Here

ESP_ARDUINO=v3.3.0+
Using BLE stack: NimBLE
Starting BLE
Now you can Connect from your phone (pw=123456)
[Serial Commands: d=Display Bonds, e=Erase All-Bonds, z=reset_NVS]
d->getNumBonds=0

Other Steps to Reproduce

No response

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

• I confirm I have checked existing issues, online documentation and Troubleshooting guide.

[Jason2866]

The behaviour is as expected. The sdkconfig(s) in the Arduino Lib Builder are not set to store BLE data in NVS.

[Rob58329]

@Jason2866 : "The behaviour is as expected. The sdkconfig(s) in the Arduino Lib Builder are not set to store BLE data in NVS."

Can you clarfy this as:

(a) On the ESP32(orig) using Bluedroid BLE this BLE_Paring_Data IS saved and you don't need to manually re-enter a paring code and rebond after every boot (this is only an issue when using the NimBLE BLE now used on the ESP32C3/ESP32S3 etc)

and (b) The "Server_secure_static_passkey.ino" example sketch says "Clear NVS to remove any cached pairing information"

and (c) I would have assumed that it would be essentual to store BLE_Paring_Data in the NVS so bond information is saved?

[Jason2866]

To save settings in NVS needs explicit set in sdkconfig when using NimBLE. There are no such settings in the sdkconfigs in Arduino Lib Builder.

[lucasssvaz]

It was my mistake when testing the nimble examples. I enabled CONFIG_BT_NIMBLE_NVS_PERSIST locally but didnt open a PR for the lib builder. Thanks for the heads up.

[Rob58329]

@lucasssvaz

NB. Your fix to "github.com/espressif/esp32-arduino-lib-builder/pull/320" on 15Sep25 does not seem to have effected
"github.com/espressif/arduino-esp32" yet, as at 16Sep25, as the latest "github.com/espressif/arduino-esp32" download (@2pm GMT 16Sep25) still does not save in NVS?

[lucasssvaz]

New libraries still not merged yet. Should be merged in the next couple days.