Home Assistant -> Mosquitto Brocker bridge to HiveMQ -> Step by step?

Hello,
I want to bridge my MQTT broker (Mosquitto) as a client to HiveMQ. I have found dozens of discussions but never a simple and accurate description that works. Several times my Mosquitto broker stopped working and I had to restore HA.
Is there a document that covers this step by step for one of the latest versions of HA?
Thank you in advance for your help.
Best regards.

Are you having problems installing MQTT?

NO. My MQTT installation using Mosquitto works very well. I just want to learn how to set up a bridge from Mosquitto Broker to HiveMQ.

Aha, a Hive question. Maybe see the vendor documation at:

Hello,

Thank you for the link. I did review that help section, and it does indeed refer to Mosquitto, but not specifically to Mosquitto as used within Home Assistant. I also tried to apply it based on my understanding; however, in the end, my Mosquitto instance in Home Assistant stopped working entirely, and I had to restore it.

That’s why I decided to ask this question on the forum.

Nevermind.