Multiple VLAN's on a single Switchport

Unanswered Question
Jan 28th, 2008

We are just in the process of rolling out Nortel IP phones but are a little confused on the VLAN apsect and Nortel aren't helping much.

Basically the IP phone needs to go into vlan 2 but the switchport is already in vlan 10 for data, how do I configure the switchport to allow both VLAN's and I assume that the Nortel phone will automatically put the PC into the non Phone VLAN and not the native VLAN 1?

Any help would be much appreciated.



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Overall Rating: 4.8 (4 ratings)
Edison Ortiz Mon, 01/28/2008 - 08:15


Your switchport configuration will use a trunk, not an access port nor voice vlan.

You have 2 options:

1) access vlan and auxiliary vlan (voice vlan)

2) trunk switchport and make sure the data vlan is the native vlan.

I believe Nortel supports option 1 (Cisco phones definitely do). If option 1 does not work, option 2 definitely works.



royalblues Mon, 01/28/2008 - 20:53

I agree using a trunk but the voice vlan will be used once the phone gets the parameters from the data vlan initially (eg option 176 in avaya)

However i agree that the recent nortel phones need not require trunk configurations and option one would work. I tested it just now but i have some old phone models which do not unless trunk is configured


jonhill Tue, 01/29/2008 - 00:17

Thanks everyone, our Nortel phones require a trunk as I've tried it with a voice vlan and and configuring the native VLAN for data works great. I was just missing the native VLAN and how to configure it.

Ken Clute Mon, 03/17/2008 - 12:02


I have a very similar issue in trying to get Nortel IP phones to work correctly with a C3560 switch. Can you send me a quick excerpt of your IOS config for the VLAn section? You mention it works by configuring the native vlan, so i'd be curious to see how configured.

jonhill Tue, 03/18/2008 - 01:44


Originally we changed the native VLAN on each switch port but had to look for a different solution as Windows DHCP and XP clients wouldn't work properly with this solution, what we ended up with is below which works great.

interface FastEthernet0/1

switchport mode access vlan 6

switchport voice vlan 2

mls qos trust cos

auto qos voip trust

spanning-tree portfast

spanning-tree bpduguard enable

jonhill Tue, 01/29/2008 - 00:23


Just an afterthought why do you need to configure access to VLAN 10 if your making it the default native VLAN surely everything that isn't tagged will go to the default VLAN?



royalblues Tue, 01/29/2008 - 00:30

You do not need that...

I had just pasted a configuration from one of our switches


shrikar.dange Tue, 01/29/2008 - 00:32


This command is used for a back-up purpose.Note there is no "MODE" keyword here.This command is used when trunking between switches fail.Then you can still access the vlan 10 on this interface.



shri :)


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