ARUBA 2920 Causing Network Loops

[mcelliers]

Hi I am currently Replacing two Cisco 3560 switches with two ARUBA Stacks.  In the network I have the 2 Cisco 3560 Switches two Cisco 2960 Switches and two rings of 9 x Moxa 510A switches. There is a dual Agregated (LACP) link between the two Csico 3560 switches. Both the Cisco 2960 Switches and the 2 Moxa Rings is connected to Both Cisco 3560 Switches.

Each Cisco 3560 Swich had a link to two the Other Cisco 2920 Switches. Each Cisco 3560 Switch had a fibre link to two switch rings with 9 Moxa Switches Each.

I replacaced the two Cisco3560 switches with two Aruba 2920-48G Stacks and enabled MSTP on both stacks.

As soon as I add the redundant connections, the whole network falls over due to network loops.

What else should I Configure on the Aruba switches to allow for the Redundant links to work?

Please see the Network Layout in the link below (dot knkow how to add image to this topic)

https://drive.google.com/drive/folders/0B3ynFiplWbn2b21hTjBCV2hsVkk?usp=sharing

Thank you in advance..

[Vince-Whirlwind]

What are the STP priorities on each of those devices?

Are the STP versions compatible?