Keep getting Failed to secure connection error

[joeyh]

Hi,

Using the gls example, as soon as I try to connect to it using NRF Connect on my iPhone, I get the "Failed to secure connection.  Disconnecting." error.  Once the error starts, it keeps loops forever like below:

 app: Glucose example started.
 app: Fast advertising
 app: Connected
 app: Failed to secure connection. Disconnecting.
 app: Fast advertising
 app: Disconnected
 app: Connected
 app: Start encryption
 app: Failed to secure connection. Disconnecting.
 app: Fast advertising
 app: Disconnected
 app: Connected
 app: Failed to secure connection. Disconnecting.
 app: Fast advertising
 app: Disconnected
 app: Connected
 app: Failed to secure connection. Disconnecting.
 app: Fast advertising
 app: Disconnected
 app: Connected
 app: Failed to secure connection. Disconnecting.
 app: Fast advertising
 app: Disconnected
 app: Connected
 app: Start encryption
 app: Failed to secure connection. Disconnecting.
 app: Fast advertising
 app: Disconnected

It seem like I am getting the "PM_EVT_CONN_SEC_FAILED" event before the Security Request timer is timed out, i.e. before encryption begins.

Before I had these errors, the pairing code was able to work once.  But, since I the errors begin to happen as soon as I deleted the bond (by pressing Key#2 while restarting the firmware).

I tried erase the flash, and reload the firmware, but no difference, the error still happens.

Any idea on how I can get this pairing code to work again will be greatly appreciated.

Thanks,

Joseph

[Harry Wei]

Hi,Sir,

New problem:

First of all, i do the same options with  joeyh:"deleted the bond on iOS side, after that, when I try to connect & do pairing on the peripheral side, the device will always get a PM_EVT_CONN_SEC_FAILED event......................"

add these codes you provided in nRF5_SDK_15.2.0_9412b96\examples\ble_peripheral\ble_app_ancs_c\pca10040\s132\ses example(No other modifications)

  case PM_EVT_CONN_SEC_CONFIG_REQ:
{
// Allow pairing request from an already bonded peer.
pm_conn_sec_config_t conn_sec_config = {.allow_repairing = true};
pm_conn_sec_config_reply(m_conn_handle, &conn_sec_config);
} break;

there wil be a error on the API(location is  on main.c line 406 )
ret = pm_device_identities_list_set(m_whitelist_peers, m_whitelist_peer_cnt);
if (ret != NRF_ERROR_NOT_SUPPORTED)
{
APP_ERROR_CHECK(ret);
}

the err_code = 0x3205 , unknown error.

that looks strange, do you have any solution? 

Best Wishes！

[Vidar Berg]

Hi, this is related to handling of the whitelist. Error 0x3205 corresponds to BLE_ERROR_GAP_DEVICE_IDENTITIES_DUPLICATE. Please see this thread for more details and workaround: https://devzone.nordicsemi.com/f/nordic-q-a/27931/sdk-ancs-bonding-allow_repairing-sdk12-2-to-sdk14-2