[c-nsp] Voice VLAN Question - QOS

[Paul Stewart]

Hi there...

We have a network of about 60-65 desktops and each one now has an IP phone
(mixture of phones - mainly Snom and Aastra) ... we I've been researching
the Voice VLAN option as a possible QOS enhancement...

I've configured a test port like this:

interface FastEthernet0/8
 description xxxxxxxxx
 switchport trunk allowed vlan 101,102
 switchport mode trunk
 switchport voice vlan 102
 switchport priority extend cos 5
 spanning-tree portfast


VLAN 101 is data and VLAN 102 is voice ... 

Is this the correct way to do it?  Does my configuration above make cos 0
for data and cos 5 for voice automatically without honouring whatever the
phone defaults to?

On the trunk ports between switches how do I make sure cos 5 gets passed
through?

Finally, when it reaches the switch facing our Cisco ASA it's broken into
ports (one for data and one for voice) - is there a way to flag cos=5 for
everything off a port?  I've opened a ticket at Cisco to understand how the
ASA handles cos values... they have told me so far that it just passes
through without any configuration required but I'm thinking there must be
more to it...;)

Sorry for all the questions... been reading a lot on this and want to make
sure my reading = good configuration..

Paul