# Can Ignition subscribe and discover tags from any MQTT topic?

**URL:** <https://forum.inductiveautomation.com/t/can-ignition-subscribe-and-discover-tags-from-any-mqtt-topic/52926>\
**Category:** Ignition\
**Created:** [November 10, 2021, 4:40pm UTC](https://forum.inductiveautomation.com/t/can-ignition-subscribe-and-discover-tags-from-any-mqtt-topic/52926 "2021-11-10T16:40:37Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![Todd\_Warrington](https://avatars.discourse-cdn.com/v4/letter/t/e5b9ba/32.png) [@Todd\_Warrington](https://forum.inductiveautomation.com/u/Todd_Warrington)\
**Post date:** [November 10, 2021, 4:40pm UTC](https://forum.inductiveautomation.com/t/can-ignition-subscribe-and-discover-tags-from-any-mqtt-topic/52926/1 "2021-11-10T16:40:37Z")

</div>

I am trying to figure out the process of “connecting” a gateway device that can publish MQTT messages, so that Ignition can discover the tags. Do I need to “Sparkplugify” the topics and payloads first?

---

<div class="post-metadata">

**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [November 10, 2021, 4:44pm UTC](https://forum.inductiveautomation.com/t/can-ignition-subscribe-and-discover-tags-from-any-mqtt-topic/52926/2 "2021-11-10T16:44:22Z")

</div>

If you don’t use Sparkplug then you need to configure a custom namespace and manually specify which topics will be subscribed to.

[https://docs.chariot.io/display/CLD79/ME%3A+Configuration](https://docs.chariot.io/display/CLD79/ME%3A+Configuration)

---

<div class="post-metadata">

**Author:** ![Todd\_Warrington](https://avatars.discourse-cdn.com/v4/letter/t/e5b9ba/32.png) [@Todd\_Warrington](https://forum.inductiveautomation.com/u/Todd_Warrington)\
**Post date:** [November 16, 2021, 1:58pm UTC](https://forum.inductiveautomation.com/t/can-ignition-subscribe-and-discover-tags-from-any-mqtt-topic/52926/3 "2021-11-16T13:58:10Z")

</div>

Kevin,

Thanks for the info. I have another question if you don’t mind…

How do I configure a Sparkplug-compliant topic when I have a device connected to a node, that publishes to an interim MQTT broker, then another node subscribes to that interim broker and finally publishes to the main MQTT broker? Am I just interested in the final node and device ids in the chain?

Todd

---

<div class="post-metadata">

**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [November 16, 2021, 3:03pm UTC](https://forum.inductiveautomation.com/t/can-ignition-subscribe-and-discover-tags-from-any-mqtt-topic/52926/4 "2021-11-16T15:03:54Z")

</div>

> [@Todd\_Warrington](#):
>
> Am I just interested in the final node and device ids in the chain?

Yes, I think that's right. That's what the MQTT modules are going to see, and that's what would need to be organized according to the Sparkplug spec.