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Detecting loop on access switch access ports before core switch shutdowns downlinks to access switch

Andriy Sidko
Level 1
Level 1

Hi guys.

 

I have network like:

nexus 5k (core&distribution) -VPC53, po53 -> enterasys access switch stack#53 in vlan 53, lag.0.1
same nexus 5k (core&distribution)-VPC54 po54 ->enterasys access switch stack#53 in vlan 53, lag.0.1

switch 53 ports ge.1.47-48 are lagged to lag.0.1 and they uplinks to nexus po53, VPC53, rest of ports in access mode, vlan 53 members
switch 54 ports ge.1.47-48 are lagged to lag.0.1 and they uplinks to nexus po54, VPC54, rest of ports in access mode, vlan 54 members

 

situation as follow:

whenever users interconnect (I believe by mistake) to neighbor desk ports one port in vlan 53 another in vlan 54, nexus detects this look at STP shutdown. As results !90 users lost access. Log file records like:
++++++++++++++++++++++++++

079949: Oct 5 15:35:35.183 EST: %SPANTREE-2-RECV_PVID_ERR: Received BPDU with inconsistent peer vlan id 53 on Port-channel54 VLAN54.
079950: Oct 5 15:35:35.183 EST: %SPANTREE-2-BLOCK_PVID_LOCAL: Blocking Port-channel54 on VLAN0054. Inconsistent local vlan.


CAONTO1Y05-SW-01#sh spanning-tree blockedports
Name Blocked Interfaces List
-------------------- ------------------------------------
VLAN0054 Po54

Number of blocked ports (segments) in the system : 1
++++++++++++++++++++++++++

So. Question.

If I enable BPDUguard at sw53&54 access ports is it help me to shutdown just one access port whenever bpdu packet hits to it? I did it many time against of interconnecting two ports at the same switch & switch stack but right now there is two stacks can reach each other via nexus.

Thank you.

1 Reply 1

Andriy Sidko
Level 1
Level 1

disregard initial question please. I've found solution.

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