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Webcast-Catalyst9k
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why I am getting CDP-4-NVLANMISMATCH:Native vlan mismatch

why I am getting CDP-4-NVLANMISMATCH:Native vlan mismatch ?

The ports are not trunking-mode .

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Anonymous
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Re: why I am getting CDP-4-NVLANMISMATCH:Native vlan mismatch

There should be a mismatch configuration at any point.

This message is generated whenever the switch port is physically connected to another switch or router. This message is generated on the switch because the native VLAN is different on the port configured, with the one set on the neighboring switch/router port.

A trunk port configured with 802.1Q tagging can receive both tagged and untagged traffic. By default, the switch forwards untagged traffic with the native VLAN configured for the port. If a packet has the same VLAN ID as the outgoing port native VLAN ID, the packet is transmitted untagged; otherwise the switch transmits the packet with a tag.

Ensure the native VLAN for an 802.1Q trunk is the same on both ends of the trunk link. If the native VLAN on one end of the trunk is different from the native VLAN on the other end, the traffic of the native VLANs on both sides can not be transmitted correctly on the trunk. This may imply some connectivity issues in your network.

Sometimes if you have accelerated server load balancing (ASLB), the message is present so you have to disable CDP on the affected ports.

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