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BSModlinFlag for United States of America

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Shoretel QoS Configuration on Cisco Switches

I am preparing to implement a new Shoretel VOIP solution.  I currently have a L3 3560 Core switch.  Attached to that via ether-channel Trunks is (3) 2960s Stacked.  

My question is regarding using Auto Qos for the switches.  I understand these phones do not use CDP so the standard Auto QoS commands need to be modified.

Here is what I am assuming:

auto qos voip trust (Executed on both the 3560 and the 2960 stack)

Not sure what to do next (If that is even correct).

Also, how are the ether-channel trunks configured?

Sorry, but I am a newbie with QoS and the Shoretel system.  I understand QoS is a HUGE animal.... I am just looking for a very default basic configuration.
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Predrag Jovic
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So if it is unknown territory to you .. it is excellent path:
# interface range gi1/0/1 - 24, Gi1/0/28 - 37     <--- or whatever is your range
# auto qos voip trust
additionally you need to configure access ports with spanning-tree portfast command
and trunks to trust QoS markings:
# interface Po1                                      <--- on both switches (trunks)
# mls qos trust cos
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ASKER

Ok, thank you for the response.....

Question regarding the trunks.....  Do these statements get put ONLY on the INT PORT-CHANNEL of both switches or on the physical ports as well?

# interface Po1                                      <--- on both switches (trunks)
# mls qos trust cos
Command added to Etherchannel typically is automatically reflected to physical interfaces. So, adding it to port-channel should be enough, if, my some miracle that is not the case - add command also to physical interfaces. :)
Ok, got it.... and last question......

You said to add the following command inside ALL interfaces:
auto qos voip trust

Does that include the physical Trunk interfaces?
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Predrag Jovic
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This command worked fine on all of the access ports:

auto qos voip trust

But, the trunk commands did not work.  Once I enter the port-channel (int port-channel1), the following commands are not recognized:

auto qos trust dscp
mls qos trust cos

What am I doing wrong?
Have no idea what can be problem (except that I can suggest you to try issue commands under interfaces assigned to etherchannel, not under Po interface), since it is book example how to configure QoS on switch with auto QoS and how to enable qos on trunks.
interface giX
 mls qos trust {cos|dscp}
should be available commands (I use that one regularly on 2960-X). Although  mls qos trust {cos|dscp} one will only configure trunks to trust  and not to overwrite cos|dscp markings and not to do much more than that (that's why I suggested auto qos command on trunks if available - to configure other parts of qos configuration automatically) typically it should be good enough since congestion is rarely present on local network.

Please read Cisco's article - Catalyst 2960-X Switch QoS Command Reference, Cisco IOS Release 15.0(2)EX
ok, the command mls qos trust cos worked on the physical trunk interfaces.  But I still cannot issue the following command on the port channel or physical trunk iterfaces:

auto qos trust dscp

Also, my core switch does not have any VOIP devices plugged into it, so I do not need this command on any interfaces, correct?

auto qos voip trust


My assumption is issue "mls qos trust cos" on the physical trunk interfaces, and then "auto qos voip trust"  on the Access witch with the voip devices connected to it.  Also, adding "mls qos trust cos" to the trunks on the Access switch as well?
Interfaces are configured to trust cos, that should be enough.
Also, adding "mls qos trust cos" to the trunks on the Access switch as well?
Sure. By default interfaces are configured not to trust QoS markings and switch is overwriting it if trust is not set on interface. So, you need to configure trunks not to overwrite priority markings in frames/packet. Also depending on phone it can be configured to set priority in L2 (cos) or L3 (dscp). Auto qos should create mapping cos to dcsp (and vice versa).