Userlevel 4
Create Date: May 20 2012 9:59PM

Hi Friends,

Can anyone help me with mapping tag and untag port with Access and trunk config of Cisco?

For example is untaged - access port in Cisco ?

tagged port - trunk port in cisco?

Or how this tag untag logic applies to server and switch connection?


(from Bhaumik_Trivedi)

3 replies

Userlevel 4
Create Date: May 21 2012 12:10AM


from my knowledge with Cisco it is correct (switchport mode access -untagged port, switchport mode trunk - tagged port for trunking as in 802.1q).

You should try the Legacy CLI module from Extreme (it is Cisco like CLI commands for Extreme switches): http://extremenetworks.com/libraries/...

Also on the Extreme website there are a few tech courses for free : http://extremenetworks.com/solutions/... (try the EXOC (Online): ExtremeXOS: Operation and Configuration),

Or the Training Guides : http://extremenetworks.com/solutions/... (try the ENA12.6 switch operation, config & management)

Let me know if you need further help.



(from Teodor_Fuica)
Userlevel 4
Create Date: May 21 2012 7:08AM


Not sure if I would claim Cisco is correct or not correct simply a different way to accomplish the same thing.

In Cisco's word any port where more than one VLAN lives is considered a "Trunk " port. With their implementation they tag packets for all VLANs except their native VLAN which remains untagged.

In Extreme's implementation we do not have a native VLAN concept. Although the standard does allow you to have an untagged VLAN on a port it is not mandatory for Extreme. It is our belief that any uplink or trunk port with many VLANs should have all VLANs tagged to minimize any issue with traffic going on the correct VLAN. Understand that the switch port just looks at the packets and if it is a tag he has then he forwards it to the correct VLAN. If the packet is untagged then it must go into the untagged VLAN. The untagged VLAN is basically the catch basin for anything. If all VLANs are tagged then any untagged packet will be dropped.

In our implementation we allow you to select which VLAN is untagged if needed. So you must explicitly tag a port on each VLAN that you want it to reside.

In comparison Cisco's access port is equal to an untagged port on Extreme meaning there is only one VLAN on the port. Cisco's "trunk" port is equivalent to a port on Extreme that is tagged with the exception that Cisco will not tag the native VLAN.

If you are connecting an Extreme switch to a Cisco switch then you need to have the VLAN that maps to Cisco's native VLAN as untagged on the port going to Cisco from Extreme.

Hope that helps.

P (from Paul_Russo)
Userlevel 4
Create Date: May 21 2012 9:15PM

Thanks you very much friends for your prompt and comprehensive responds.

I am doing implementaion on model soon, so If any issue arises I will post it back here.

Thanks again.

(from Bhaumik_Trivedi)