Stuck in connect/disconnect loop

[tallgaijin]

I'm using the sample code at https://aws.amazon.com/premiumsupport/knowledge-center/iot-core-publish-mqtt-messages-python/

When I run the code, the MQTT Test Client shows that the device is connecting and disconnecting 2-3 times per second. The disconnect reason is CLIENT_ERROR, but I'm not sure where to go from here.

$aws/events/presence/disconnected/fake-iot-device-1
June 24, 2022, 22:23:18 (UTC-0400)

{
"clientId": "fake-iot-device-1",
"timestamp": 1656123792890,
"eventType": "disconnected",
"clientInitiatedDisconnect": false,
"sessionIdentifier": "e4f0a92d-340e-45f2-9421-73a728db2977",
"principalIdentifier": "6567812a7617b6b9be2ea1527200222cb2be7944a1676573f816e321505da3ef",
"disconnectReason": "CLIENT_ERROR",
"versionNumber": 1534
}

$aws/events/presence/connected/fake-iot-device-1
June 24, 2022, 22:23:18 (UTC-0400)

{
"clientId": "fake-iot-device-1",
"timestamp": 1656123792863,
"eventType": "connected",
"sessionIdentifier": "e4f0a92d-340e-45f2-9421-73a728db2977",
"principalIdentifier": "6567812a7617b6b9be2ea1527200222cb2be7944a1676573f816e321505da3ef",
"ipAddress": "157.245.213.255",
"versionNumber": 1534
}

[tallgaijin]

I think I figured it out.

I enabled error logging in CloudWatch, which showed that I was actually getting an Authorization Error. Dug into that and found an issue in the policy. Not sure why it was giving a Client_Error message at first, but maybe this will help if anyone else has the same issue.

[uremmel420]

Hi tallgaijin,
I have a very similar issue with my M5stack Core 2 Development Board and I can't get it working.
What did you change in the policy?

[tallgaijin]

I can't remember exactly, but I think it was a missing permission. Might have been missing an iot:Connect permission?

[uremmel420]

Thanks for answering so quickly.
I just figured out what's wrong.
I needed to add every permission manually with "*" put into the resources.

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Hello! Reopening this discussion to make it searchable.

[Adesanya-Toba]

Yeah, I believe the error message could be more explicit in detailing what's happened. AWS' documentation of the 'CLIENT_ERROR' didn't provide much help either.

But yeah, I've found it's usually something to do with the policy. For example, the client trying to publish or subscribe to a topic not defined in the policy.