Can you link this image? I've been having tons of issues with the sim software and believe it to be the currently recommended image. STP is blocking ports as it should, but the underlying behavior still resembles a loop.
I've heavily simplified this topology, but here is a GNS3 post I made regarding the issues I've been having:
https://gns3.com/initiatives/aruba-cx-os-icmp-nonresponsive-with-mstp-config
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Andrew Lewandowski
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