Cisco / Spanning Tree on Access Ports from ISP

ciscoispspanning tree

Please excuse my ignorance & noobishness.

I have a switch which has two different point to point connections, these both plug into access ports & have their own VLAN.

These two point to point connections are coming from the same ISP which is causing the port to close.

I'm no expert in spanning-tree loops, and I'm scared of causing any issues. How should I manage these ports? Or is something my ISP has to handle?

*Mar 15 03:58:23 UTC: %SPANTREE-7-RECV_1Q_NON_TRUNK: Received 802.1Q BPDU on non trunk GigabitEthernet1/0/1 VLAN2050.
*Aug 15 03:58:23 UTC: %SPANTREE-7-BLOCK_PORT_TYPE: Blocking GigabitEthernet1/0/1 on VLAN2050. Inconsistent port type.
*Aug 15 03:58:24 UTC: %LINK-3-UPDOWN: Interface GigabitEthernet1/0/1, changed state to up
*Aug 15 03:58:25 UTC: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet1/0/1, changed state to up
*Aug 15 03:58:39 UTC: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet1/0/1, changed state to down
*Aug 15 03:58:40 UTC: %LINK-3-UPDOWN: Interface GigabitEthernet1/0/1, changed state to down

Thank you for your help, totally clueless over here.

Best Answer

In my opinion, you've set things up "wrong". (and so has the ISP)

Never, EVER, trust what the ISP puts on your link. If you're running a metro-e interface into a switch, everything possible should be shut off on that port -- VTP, CDP, LLDP, spanning-tree, etc. The ISP isn't part of your "enterprise", so there's no reason to exchange such information with them. Plus, CDP/LLDP will attempt to ensure port settings (including VLAN assignments) are the same.

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