RE: Voice vlan

From: Antonio Soares (amsoares@netcabo.pt)
Date: Sat Jul 14 2007 - 13:47:06 ART


With older switches, it was mandatory to have dot1q trunking.

With the 3550/3560 you don't need it.

And from the 3560 configuration guide:

+++++++++++++++++
Voice VLAN Configuration Guidelines

These are the voice VLAN configuration guidelines:

You should configure voice VLAN on switch access ports; voice VLAN is not
supported on trunk ports. You can configure a voice VLAN only on Layer 2
ports.

Note Voice VLAN is only supported on access ports and not on trunk ports,
even though the configuration is allowed.
+++++++++++++++++

But... I've seen several types of configurations and they all work:

+++++++++++++++++
Static Access
+++++++++++++++++
SW1#sh runn int g0/6
Building configuration...

Current configuration : 139 bytes
!
interface GigabitEthernet0/6
 switchport access vlan 100
 switchport mode access
 switchport voice vlan 200
 spanning-tree portfast
end

SW1#
+++++++++++++++++
Static Trunk
+++++++++++++++++
SW1#sh runn int g0/6
Building configuration...

Current configuration : 210 bytes
!
interface GigabitEthernet0/6
 switchport access vlan 100
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 100
 switchport mode trunk
 switchport voice vlan 200
 spanning-tree portfast
end

SW1#
+++++++++++++++++

And AFAIK, the IP Phones do not support DTP.

-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
Djerk Geurts
Sent: sabado, 14 de Julho de 2007 16:56
To: 'Cisco certification'
Subject: Voice vlan

When configuring a voice vlan, does the interface need trunking enabled to
support the voice vlan feature?

If so then one should check whether the interface can negotiate it or not,
if not manually enabling trunking is required. Point being I'm not sure it
would be required as I assumed the access vlan would be the native vlan (so
to speak).

Any input welcome...

--
Djerk
www.djerk.nl


This archive was generated by hypermail 2.1.4 : Sat Aug 18 2007 - 08:17:41 ART