P2P self-loop

[slicerpro]

We just inherited a network that needs a lot of cleanup. The current setup consists of a core Cisco4510 connected via a ten gig link to a Juniper EX4600 which is in turn connected to several EX3400 access switches. The problem is that the Cisco shows its one downlink as blocking for a couple of vlans but the rest of the vlans are forwarding fine:

show spanning-tree vlan 115

VLAN0115
Spanning tree enabled protocol ieee
Root ID Priority 24691
Address xxx.xxx.xxx
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 24691 (priority 24576 sys-id-ext 115)
Address xxx.xxx.xxx
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Gi2/1 Desg FWD 4 128.129 P2p
Gi2/2 Desg FWD 4 128.130 P2p
Te5/1 Desg BLK 2 128.513 P2p self-looped

show spanning-tree vlan 163

VLAN0163
Spanning tree enabled protocol ieee
Root ID Priority 32931
Address xxx.xxx.xxx
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 32931 (priority 32768 sys-id-ext 163)
Address xxx.xxx.xxx
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec

Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Gi2/1 Desg FWD 4 128.129 P2p
Gi2/2 Desg FWD 4 128.130 P2p
Te5/1 Desg BLK 2 128.513 P2p self-looped

The Cisco sees itself as the root bridge.. but all the Juniper EX3400s also see themselves as root. The EX4600 sees one of the EX I have tried removing all redundant links downstream but it has not helped. I need some ideas guys.

[balaji.bandi]

Te5/1 Desg BLK 2 128.513 P2p self-looped

Cisco Switch sees its own BPDU back, so it shows as a loop, only 2 VLANs show looped?  rest all ok, then i will look where these VLANs are propagated other switches, see any Cable loops ?  This is not necessarily the Cisco side, it can be any part of the network the loop coming from, I will start investigating where this is connected, from there start looking at branches and see where is the loop coming from?

below output give you where these ports are allocated on the cisco side, check any ports have any looops same on other switches (depends on vendor command)

show vlan 115 

show vlan 116

can you post show run inter te5/1