Wired Intelligent Edge

We have two 8320 switches, which are acting as core in our network. Active gateway, vsx is configured between both switches. all access switches are connected to these core switches via multichasis lag. I have mixed environment of aruba(2930f) and cisco(9200) on access switch side. On access switches i have configured portchannel for cisco and trunks for aruba. right now Rapid pvst is running in the enviorment for all access and core switches, which is working fine.  

On core switches we have approx 30 vlans configured. but on access side only required vlans are configured. so on MClag to portchannel/trunk only required vlans are passed. 

Since stp mode is rapid pvst in my environment, so number of instances running for stp are equal to number of vlans configured on switch. to mitigate this i wanted to implement MSTP on my environment. So that all vlans are assigned to only MSTI0 only. So i configured the mode as MSTP on primary vsx core switch. and added region name and revision number. configuration was replicated to secondary vsx core switch automatically. 

Now all of my aruba access switches 2930f are working fine. but mc lag connecting to cisco coreswitch shows blocked. and on cisco switch portchannel is shown as errordisabled due to lacp misconfiguration. since half of my network goes down. i reverted back the configuration and have to restart all the cisco switches to restore back the connectivity. 

Wanted to know if aruba cx running MSTP is compatible with cisco rapid pvst. or there is something i have missed. 

Best practice is not to mix different STP protocols. Usually it will revert to lowest common supported protocol. If your cisco switches support MSTP, then configure it also there, if not you need to use RSTP on Cisco.

But why you would like to centralize all spanning tree into one domain? Best would be to have multiple STP domains so  you will minimize impact of spanning tree convergence in the network.

RPVST is good for small number of vlans and MSTP you would use in the case of many vlans.

Best, Gorazd