05-13-2010 08:51 AM - edited 03-06-2019 11:04 AM
I saw some previous topics regarding MSTP and PVSTP interaction but I still have some uncertainties.
Also I've read the "understanding MSTP article" from cisco's website.
my setup i:
c1 -----c2
c1 needs to be root for vlan 1-20
c2 root for rest of the vlans
c1 pvst
c2 mst
trunk conf
switchport trunk enca dot1q
sw mode trunk
sw trunk allowed vlan 1,3,6
c2 mst config
instance 0 vlan 1,3,6
instance 1 vlan all except above
and when i enable the trunk i got error and link goes to blocking mode
%SPANTREE-2-PVSTSIM_FAIL: Blocking root port Gi0/24: Inconsitent inferior PVST BPDU received on VLAN 4, claiming root 24580:0022.55bb.1500
anything i am missing in my config ?
I understand that mst needs to be root bridge for all the rstp vlans but is there any alternative way around it ?
09-02-2014 04:50 AM
Did you ever get a resolution for this?
I have a situation whereby in a predominantly HP network (comware) I have a handful of Cisco switches. All running MST. The Root for all VLANs is a L3 HP Core chassis switch. Everythign is fine until you plug a new Cisco switch into the network configured with the default PVST. All the Cisco switches running MST shutdown their up-link to the Core with an error
SPANTREE-2-PVSTSIM_FAIL: Blocking root port Po1: Inconsistent Inferior PVST BPDU received on VLAN 4, claiming to be root 32772:mac address.
It is is an inferior BPDU why is the Cisco switch shutting down the port. I need to remove PVSTSIM I think?
09-02-2014 09:15 AM
PVST simulation is run on boundary ports and works in two ways:
For PVST simulation to work without failures, these two conditions must be met:
If these conditions are not met, the boundary port is put into a PVST simulation inconsistent state until the problem is corrected.
Regards
Inayath
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