01-29-2007 01:05 PM - edited 03-03-2019 03:32 PM
with auto QoS configuration like this:
interface GigabitEthernet0/4
switchport access vlan 12
switchport mode access
switchport voice vlan 15
srr-queue bandwidth share 10 10 60 20
srr-queue bandwidth shape 10 0 0 0
queue-set 2
mls qos trust device cisco-phone
mls qos trust cos
auto qos voip cisco-phone
spanning-tree portfast
I am sure PC behind IP phones will be on vlan 12 with dscp/cos reset to zero by IP phones.
but...
what about a PC connecting to this port G0/4 directly without IP phone?
will the switch detect it via CDP (it's not IP phone!) then reset COS to zero?
or blindly trust incoming COS from this user PC?
thanks!
01-29-2007 01:19 PM
The IP phone is detected via CDP. If there is no Ip phone, the traffic will not be trusted.
Traffic will flow via the access-vlan (12) with dscp & cos both reset to zero.
Regards,
Leo
01-29-2007 02:10 PM
thanks!
We also have C6500 SUP32 running IOS without AutoQoS support.
L2S19(config-if)#mls qos trust ?
cos cos keyword
dscp dscp keyword
extend extend keyword
ip-precedence ip-precedence keyword
is it even possible to configure the SAME function fo Auto QoS manually?
you can not specify "mls qos trust device" any more
I think no because switch won't check with CDP discovery (IP phone or not) and determine trust boundry.
let me know!
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