Twilio SMS inbound configuration

Ignition
1

Hi all,

I’m implementing SMS alarm acknowledgements in Ignition using the built-in Twilio notification profile, but I’m stuck on the ACK step.

Environment

  • Ignition Gateway: 8.3.2

  • Publicly accessible gateway host

  • Gateway Web Server: HTTPS enabled on port 8043 (HTTP on 8088)

What I’m trying to do

  • Use Ignition’s Twilio SMS notification profile with “Acknowledgement Allowed” enabled, so users can reply to the SMS with the acknowledgement code and Ignition will acknowledge the alarm.

Inbound webhook endpoint

  • Twilio is configured to hit: https://:8043/system/twilio

  • /system/twilio behavior from my machine:

    • GET returns 405 Method Not Allowed (expected)

    • POST returns 200 OK (verified with curl using x-www-form-urlencoded payload)

Twilio / Ignition settings (current)
Ignition Twilio account settings

  • HTTPS Enabled: true

  • Inbound Validation Enabled: false (see below)

Twilio configuration

  • Phone Number:

    • Assigned to a Messaging Service AND a TwiML App

    • Not using per-number webhooks directly

  • Messaging Service:

    • Incoming Messages: “Defer to sender’s webhook”

  • TwiML App:

    • Messaging URL: https://:8043/system/twilio

Observed behavior

  • I receive alarm SMS notifications correctly.

  • When I reply with the acknowledgement code, the alarm is NOT acknowledged in Ignition.

  • When Inbound Validation Enabled = false:

    • Twilio Console shows no webhook errors

    • Ignition gateway logs show nothing (no obvious twilio/ack processing)

  • When I set Inbound Validation Enabled = true and test:

    • Twilio starts logging an error 11220: “SSL/TLS Handshake Error”

    • Twilio shows the request going to: https://:8088/system/twilio (HTTP port), even though I’ve configured 8043.

    • Error excerpt:
      “Twilio was unable to fetch content from: https://:8088/system/twilio
      Error: Connection reset by peer over TLS, assuming that this is a handshake failure
      Request URI: https://:8088/system/twilio
      SSL Version: TLSv1.3”

Questions

  1. For Ignition’s Twilio SMS ACK flow, should the inbound webhook be ONLY configured in one place (Messaging Service vs TwiML App vs per-number), and can having both a Messaging Service and TwiML App assigned cause the inbound reply to bypass /system/twilio or be routed differently?

  2. Is “Defer to sender’s webhook” appropriate for inbound ACK replies, or should the Messaging Service be explicitly set to “Send a webhook” to /system/twilio?

  3. When Inbound Validation Enabled is enabled in Ignition, what determines the port Twilio ends up calling (why would it switch to 8088)?

  4. Are there any specific Ignition log categories or settings I should enable to see Twilio inbound/ACK processing?

Any guidance on the correct Twilio + Ignition configuration for inbound SMS acknowledgement would be appreciated.

Thanks.

2

Setting Ignition loggers to Debug mode, I do get callbacks from Twilio in Ignition logs. However, they fail to validate. In Twilio, I keep getting 11220 - SSL/TLS Handshake Error because for some reason, it keeps trying to POST to https://<gateway>:8088/system/twilio even though I had the TwiML app set to 8043.

image