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New Member

"vlan dot1q tag native" end-to-end QoS switched network

Guys,

Can I use this in my switched network design, (without using 802.1q tunneling as documentation always seems to mention this vlan in a vlan scenario???)

I have native vlans and I want to act upon the 802.1p CoS field from end-to-end in my switched network. If the packet happens to be in a native vlan, I cannot do this.

ie

pc------accessswitch--------distswitch/rtr

between access and distribution, there is a dot1q trunk, and the native vlan is the vlan what the pc is in

Choices.

run this comand vlan dot1q tag native

dont have a native vlan, ie have vlan 1 (default as native) on the dot1q up to the dist

or act only upon L3 dscp

Can anyone help?

Many thx,

Ken

2 REPLIES
Blue

Re: "vlan dot1q tag native" end-to-end QoS switched network

in order to use the dot1p fields in the 2byte tag of the ethernet frame, you must have that port configured for dot1q. aka...a trunk.

once configured as a trunk, the port can recognize the dot1p fields and read their data. without a port as a trunk, it can only read a normal ethernet frame, which does not contain a 2byte tag for dot1q/p.

also, the 'native' vlan is one that does not require the 2byte tag for dot1q/p. this is why default native config does not read the tag.

New Member

Re: "vlan dot1q tag native" end-to-end QoS switched network

Hi there,

Many thx for that. This I understand and the question was really, if I wanted to use a dot1p tag in the dot1q header, but the vlan that the PC was on was the same vlan as the native vlan on the dot1q trunk, what is the best option to ensure I can action qos.

Just trust dscp on the trunks always

tag the native,

or just dont run a native vlan

I hope this makes sense. Sorry if I was a little confusing b4.

Thx

Ken

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