Spanning-tree Anamoly - MST

[kwakalack]

Hi Community,

I have a Nexus 3064 connected to a 3750X via trunk without bpduguard; nothing that'll prevent spanning-tree communication. But even though I configured priorities and bounced ports, etc, I can't get the Nexus to become the root for all instances. Currently, both switches are roots for all instances. Also, all other 3750X switches connected to the Nexus with the same MST configurations are correctly registering the Nexus as the root for all instances. Has anyone come across this before by any chance? Thank you in advance and for your time!

Here are their respective MST configs:

Nexus 3064:

spanning-tree mode mst
spanning-tree mst 0 priority 4096
spanning-tree mst 1-4 priority 16384
spanning-tree mst configuration
name region1

revision 0

instance 1 vlan 2000-2199
instance 2 vlan 3000-3399
instance 4 vlan 2-1999

show spanning-tree root:

MST0000 4096 74a2.e653.c001 0 2 20 15 This bridge is root
MST0001 16385 74a2.e653.c001 0 2 20 15 This bridge is root
MST0002 16386 74a2.e653.c001 0 2 20 15 This bridge is root
MST0004 16388 74a2.e653.c001 0 2 20 15 This bridge is root

Port connected to 3750X config:

interface Ethernet1/16
switchport mode trunk

3750X:

spanning-tree mode mst
spanning-tree mst configuration
name region1

revision 0

instance 1 vlan 2000-2199
instance 2 vlan 3000-3399
instance 4 vlan 2-1999
spanning-tree mst 0-4 priority 28672

show spanning-tree root:

MST0 28672 d48c.b577.fd80 0 2 20 15
MST1 28673 d48c.b577.fd80 0 2 20 15
MST2 28674 d48c.b577.fd80 0 2 20 15
MST4 28676 d48c.b577.fd80 0 2 20 15

Port connected to Nexus config:

interface TenGigabitEthernet1/1/1
switchport mode trunk

[MHM Cisco World]

are you sure the port of NSK connect to SW is not config as Edge port ??

[kwakalack]

I have provided the config on the port

[MHM Cisco World]

you only config port as trunk, make sure it not edge. 
I think the NSK and SW not exchange the BPDU and hence each one declare in STP domain I am the root. 
the BPDU is missing. 

[kwakalack]

I just said I already provided the config of the ports. The only line of config is switchport mode trunk

[kwakalack · Accepted solution]

This has been resolved. Vlan 1 was shutdown on the access switch. MST exchanges bpdus via native vlan and the trunk port is using vlan 1 as native.