# How to use unified namespace **URL:** \ **Category:** Maker\ **Tags:** perspective\ **Created:** [April 23, 2024, 8:31pm UTC](https://forum.inductiveautomation.com/t/how-to-use-unified-namespace/89318 "2024-04-23T20:31:22Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Vidar\_Hetlelid](https://avatars.discourse-cdn.com/v4/letter/v/dfb087/32.png) [@Vidar\_Hetlelid](https://forum.inductiveautomation.com/u/Vidar_Hetlelid)\ **Post date:** [April 23, 2024, 8:31pm UTC](https://forum.inductiveautomation.com/t/how-to-use-unified-namespace/89318/1 "2024-04-23T20:31:22Z")
Hi there, I wanna test out unified namespace. As of my understanding i could use MQTT as unified namespace, in my case hiveMQ. Lets say I want to start a motor from Nodered, to do so i can publish to test/motor1:on. Ignition can then subscribe to that topic and read that motor is on using MQTT engine. But how can I send a command from Ignition to turn it off? Any tips and tricks regarding this is very appreciated. 🙂 ---
**Author:** ![kcollins](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kcollins/32/19646_2.png) [@kcollins](https://forum.inductiveautomation.com/u/kcollins)\ **Post date:** [April 23, 2024, 8:40pm UTC](https://forum.inductiveautomation.com/t/how-to-use-unified-namespace/89318/2 "2024-04-23T20:40:56Z")
If you're using Custom Namespace to subscribe to vanilla MQTT topics using MQTT Engine, you'll need to use [`system.cirruslink.engine.publish`](https://docs.chariot.io/display/CLD80/ME%3A+Python+Scripting) scripting functions to propagate writes back to the broker. ---
**Author:** ![Vidar\_Hetlelid](https://avatars.discourse-cdn.com/v4/letter/v/dfb087/32.png) [@Vidar\_Hetlelid](https://forum.inductiveautomation.com/u/Vidar_Hetlelid)\ **Post date:** [April 23, 2024, 8:44pm UTC](https://forum.inductiveautomation.com/t/how-to-use-unified-namespace/89318/3 "2024-04-23T20:44:49Z")
Uhm, okay thanks. Yes, its custom namespace and vanilla MQTT. But, i want to use sparkplug B. What do you think is the best way of doing that (industrial way) ? (I wan't to learn about the industrial way of using MQTT/sparkplug and ignition) ---
**Author:** ![kcollins](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kcollins/32/19646_2.png) [@kcollins](https://forum.inductiveautomation.com/u/kcollins)\ **Post date:** [April 23, 2024, 8:59pm UTC](https://forum.inductiveautomation.com/t/how-to-use-unified-namespace/89318/4 "2024-04-23T20:59:14Z")
It is pretty easy on the MQTT Engine side of things--it will see edge nodes/devices as they publish their births and populate tags in the MQTT Engine tag provider. Note that MQTT Engine blocks outbound writes by default--it is a configuration setting in the Ignition web UI. Once configured, you can write to the tags and MQTT Engine will handle sending the appropriate DCMD/NCMD messages with the new values. ---
**Author:** ![Vidar\_Hetlelid](https://avatars.discourse-cdn.com/v4/letter/v/dfb087/32.png) [@Vidar\_Hetlelid](https://forum.inductiveautomation.com/u/Vidar_Hetlelid)\ **Post date:** [April 23, 2024, 9:01pm UTC](https://forum.inductiveautomation.com/t/how-to-use-unified-namespace/89318/5 "2024-04-23T21:01:17Z")
Thanks! i'll check it out. Isn't it normal to write back? ---
**Author:** ![kcollins](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kcollins/32/19646_2.png) [@kcollins](https://forum.inductiveautomation.com/u/kcollins)\ **Post date:** [April 23, 2024, 9:03pm UTC](https://forum.inductiveautomation.com/t/how-to-use-unified-namespace/89318/6 "2024-04-23T21:03:31Z")
> [@Vidar\_Hetlelid](#): > > Isn't it normal to write back? Yes. I think there are some safety benefits from having the outbound writes disabled by default. ---
**Author:** ![Vidar\_Hetlelid](https://avatars.discourse-cdn.com/v4/letter/v/dfb087/32.png) [@Vidar\_Hetlelid](https://forum.inductiveautomation.com/u/Vidar_Hetlelid)\ **Post date:** [April 23, 2024, 9:05pm UTC](https://forum.inductiveautomation.com/t/how-to-use-unified-namespace/89318/7 "2024-04-23T21:05:38Z")
Allright, Now its enabled 🙂 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/d/5/d5eedbc4042c5c038b701d899a1a4b228a7ebd0c.png) Not sure what I need to do in order for the data from node red to show up... This appears in ignition though, but not the data itself: ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/9/4/941f8d1640b5d9b0b452655afcae189affa1abcf.png) ---
**Author:** ![kcollins](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kcollins/32/19646_2.png) [@kcollins](https://forum.inductiveautomation.com/u/kcollins)\ **Post date:** [April 23, 2024, 9:09pm UTC](https://forum.inductiveautomation.com/t/how-to-use-unified-namespace/89318/8 "2024-04-23T21:09:08Z")
You might try to use an MQTT test tool to make sure that your Node-RED setup is behaving as a proper SparkplugB edge node. There are some loggers on the Ignition side that you might be able to turn up to see more detail, too.