Copyright ©

Mongoose OS Forum

ATTENTION! This forum has moved to:

Do not post any new messages.

What does "MQTT TCP connect error (-688)" mean?

ulsoulso Stockholm

Q is in the title.

A couple of weeks ago I built the mongoose-os firmware for a new board, and I successfully managed to get 10 of them connected to AWS IoT.
Now when I try to get a few additional boards connected to AWS IoT it doesn't seem to work at all.
I have not changed the firmware in any way. I use the same file as before when flashing the boards.

When using the mos console command I see the following repeatedly:

[Apr 26 19:14:06.493] mgos_mqtt_global_con MQTT connecting to
[Apr 26 19:14:06.881] sl_set_ssl_opts      CERTIFICATE_FILE_NAME aws-cc3220_xxxxxx.crt.der -> 0
[Apr 26 19:14:06.888] sl_set_ssl_opts      PRIVATE_KEY_FILE_NAME aws-cc3220_xxxxxx.key.der -> 0
[Apr 26 19:14:06.896] sl_set_ssl_opts      CA_FILE_NAME ca.der -> 0
[Apr 26 19:14:07.454] mgos_mqtt_ev         MQTT TCP connect error (-688)
[Apr 26 19:14:07.459] mgos_mqtt_ev         MQTT Disconnect

So, the only possible difference between now and a couple of weeks ago might be the mos utility. I am using version 2.1 (Homebrew) of the mos utility.

Sign In or Register to comment.