Spanning Tree MSTP vs RSTP

[Haval.Darwesh]

Hello;

I have a network diagram shown in the first image, which is consist of two regions, the first region includes multiple switches with a Cisco C4500X as core switch which has been deployed previously, currently the new region has been installed with multiple switches that has a C9500X as the core switch.

First region uses MSTP protocol while the new region use RSTP protocol. STP configuration of both core switches are attached named 03 and 04.

Now, the issue is no any VLANs can communicate between the region, it gives the error message:

blocking designated port: inconsistent superior pvst bpdu received on VLAN 10 claiming root 10

I have attached error message image named 02.

what is the issue please? and how to solve it?

[MHM Cisco World · Accepted solution]

First check in which pvst or mst the root is 

Then change vlan from2-1023 priority according to what you get 

https://www.cisco.com/c/en/us/support/docs/lan-switching/multiple-instance-stp-mistp-8021s/116464-configure-pvst-00.html

This link explains what happened in your network 

MHM

[Haval.Darwesh]

let me check the link and your solution, I appreciate

[Haval.Darwesh]

Dear;

thanks for your response and help, it worked as mentioned from the link. thanks a lot

my problem solved

[MHM Cisco World]

You are so welcome 

MHM

[liviu.gheorghe]

Hello @Haval.Darwesh ,

no diagrams are attached.

[Haval.Darwesh]

sorry, I forgot to attach the diagram