qos trust boundary

[Ken Hagen]

Hello,

I need to configure several switches to trust dscp of PCs that are configured with various dscp markings for softphone applications.  The command I was given was mls qos trust.  The switches I have do not have that command.  I need to also trust the Cisco phones that will be connected.  Upon some research it appears I need to configure "switchport priority extend trust".  With that command it appears that the devices on the port are trusted.  I try to also configure "qos trust device cisco-phone", but the output for that is not what I expected.  Can someone explain?  I want to trust both cisco phone and softphone markings.  See below:

switch(config-if)#switchport priority extend trust
switch(config-if)#do sh run int g3/13
Building configuration...

Current configuration : 926 bytes
!
interface GigabitEthernet3/13
description x
switchport access vlan x
switchport mode access
switchport voice vlan x
switchport priority extend trust
qos trust extend
spanning-tree portfast edge
end

switch(config-if)#do sh qos int g3/13
Operational Port Trust State: Trusted
Trust device: none
Default DSCP: 0 Default CoS: 0
Appliance trust: trusted

switch(config-if)#qos trust device ?
cisco-phone Cisco IP Phone
cts Cisco-telepresence
ip-camera Cisco video surveillance camera
media-player Cisco Digital Media Player

switch(config-if)#qos trust device cisco-phone ?
<cr>

switch(config-if)#qos trust device cisco-phone
CSW-SMT-14-ACC(config-if)#do sh qos int g3/13
Operational Port Trust State: Untrusted
Trust device: cisco-phone
Default DSCP: 0 Default CoS: 0
Appliance trust: trusted

[Ken Hagen · Accepted solution]

Found the answer to my own question. Reason is because I do not have a cisco phone connected.  

[Roger Kallberg]

Glad you got this “resolved”.

Never even contemplated that you would not have a phone connected when you looked at the trust status for a port that is set to trust a phone if it’s connected, as that would in a scene defeat the intent of the command as such.

Isn’t it somewhat obvious that this would be the outcome of this specific show command with your criteria’s in mind?

[Ken Hagen]

We have softphones. Many people are not at work and don't need a phone on their desk. I was trying to be pro-active in case a phone was ever installed at the location in the future.  Although we do have some non-cisco voip phones that are being swapped out for cisco phones which throws another variable into it, but mostly softphones. Thanks for your comment.