Native VLAN mismatch discovered on FastEthernet1/10 (20)

Unanswered Question


Why the following msgs appears?I have normal access ports with different vlan on the same switch as i dont have any trunk link with 802.1Q encaps?

*Mar  1 00:46:28.515: %CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discovered on FastEthernet1/10 (20), with SW1 FastEthernet1/7 (1).
*Mar  1 00:46:28.571: %CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discovered on FastEthernet1/7 (1), with SW1 FastEthernet1/10 (20).

Thanks a lot

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Overall Rating: 5 (2 ratings)
Peter Paluch Mon, 05/10/2010 - 02:13
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If I interpret the logging messages correctly then it seems you have a loop in your network: there is a loop between your interfaces Fa1/10 and Fa1/7. They are both in different VLANs but they both exchange CDP packets that somehow leak from one port to another. Each CDP packet carries the number of the native or the access VLAN the port is in.

Double check the connections in your network.

Best regards,



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