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New Member

trunk port vs. access port

What are the danger of this configuration on a port that connects to a server?

switchport access vlan 100

switchport trunk encapsulation dot1q

switchport mode trunk

Hall of Fame Super Bronze

Re: trunk port vs. access port

The switch will try to negotiate a trunk connection during the initial connection.

If the negotiation fails, it falls back to the access vlan. In your case, your server will use Vlan 100 for this connection.

There isn't any danger but you may experience a delay on the port becoming active due to the negotiation. I recommend configuring the port for mode access and remove the encapsulation from the configuration.

Now, if your server NIC is able to use 802.1q, then the switchport will be trunked and all Vlans except for Vlan 1 will be tagged. Per your configuration, the trunk native Vlan is Vlan 1.




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New Member

Re: trunk port vs. access port

the native vlan will be 100 , not default 1.

the server will become int vlan 100 .

the trunk default permit all traffic date out of the port ,the server will process more useless date.