Krishna, I added the "mls qos srr-queue output dscp-map" commands so that the 
cos-map and dscp-map match with equivalent values.  This is not a requirement 
as your question is stated.

In addition for the link to the router you need:
mls qos trust dscp

On the server ports:
mls qos trust dscp

On the phone ports:
mls qos trust cos
mls qos trust device cisco-phone

This is assuming there are no other stated requirements for marking traffic 
requiring class-maps and policy-maps and service policies.

Michael Sears

From: Krishna [mailto:vinayak_...@yahoo.com]
Sent: Sunday, October 14, 2012 6:59 PM
To: Sears, Michael (msears)
Cc: Online Study
Subject: Re: LAN QOS QUESTION

michael,

thanks for your input on this query.. i am using 3750 switch provided by 
proctor labs.. I am well aware lan qos queuing and thresholds , but not sure 
where should i have to keep those values unless if they are explicitly stated.

adding to that question, i assume i need to put "mls qos trust dscp" for the 
traffic coming from router to switch isn't it?? I see some guys putting as mls 
qos trust cos which i feel incorrect since layer 2 to laye3 mappings were done 
using cos-dscp mapping. please correct me if i am wrong.

thank you
krishna.

________________________________
From: "michael.se...@compucom.com<mailto:michael.se...@compucom.com>" 
<michael.se...@compucom.com<mailto:michael.se...@compucom.com>>
To: ccie_voice@onlinestudylist.com<mailto:ccie_voice@onlinestudylist.com>
Cc: vinayak_...@yahoo.com<mailto:vinayak_...@yahoo.com>
Sent: Sunday, October 14, 2012 4:50 PM
Subject: RE: LAN QOS QUESTION


On a Cisco 3750 --> I used the Enterprise_QoS_SRND [1] pages 105 through 112 to 
put together the following QoS configuration to meet your stated requirements.  
I would recommend you follow the SRND when writing your QoS configuration it's 
pretty much cut and paste.

Requirements:
assign cos 5 to priority queue
assign cos 3 4 to queue 2
cos 4 exceed 60% should be dropped

Solution:
mls qos
mls qos map cos-dscp 0 8 16 24 32 46 48 56
mls qos srr-queue output cos-map queue 1 threshold 3 5
mls qos srr-queue output cos-map queue 2 threshold 3 3
mls qos srr-queue output cos-map queue 2 threshold 1 4
mls qos srr-queue output dscp-map queue 1 threshold 3 46
mls qos srr-queue output dscp-map queue 2 threshold 3 24
mls qos srr-queue output dscp-map queue 2 threshold 1 32
mls qos queue-set output 1 threshold 2 60 100 100 100

Note how cos 3 and 4 are both in queue 2 but in different thresholds.  Then 
since cos 4 is in threshold 1 it is marked down to 60% to discard cos 4 above 
60%.

Hope this helps.  Keep in mind QoS will vary depending on switch type.  INE has 
some great Videos on understanding LAN QoS and the relationships between Queues 
and Thresholds and related configurations.

http://www.cisco.com/en/US/docs/solutions/Enterprise/WAN_and_MAN/QoS_SRND/QoS-SRND-Book.html

What switch type are you using?

Michael Sears

Message: 1
Date: Sat, 13 Oct 2012 18:40:10 -0700 (PDT)
From: Krishna <vinayak_...@yahoo.com<mailto:vinayak_...@yahoo.com>>
To: Online Study 
<ccie_voice@onlinestudylist.com<mailto:ccie_voice@onlinestudylist.com>>
Subject: Re: [OSL | CCIE_Voice] lan qos- cos 5 threshold 1 in queue 1
    doesn't show in running config
Message-ID:
    
<1350178810.93468.yahoomail...@web164602.mail.gq1.yahoo.com<mailto:1350178810.93468.yahoomail...@web164602.mail.gq1.yahoo.com>>
Content-Type: text/plain; charset="iso-8859-1"

hi guys,

i was wondering whether i am doing right way of doing lan qos or not ?? the 
requirements are assign cos 5 to priority queue , cos 3 4 ?to queue 2 with 60% 
exceed of cos 4 should be dropped. so here is my configuration for that

mls qos?
mls qos srr-queue output cos-map queue 1 threshold 1 5 mls qos srr-queue output 
cos-map queue 2 threshold 2 3 mls qos srr-queue output cos-map queue 2 
threshold 1 4

mls qos queue-set output 2 threshold 3 60 100 100 272


when i issued show run | i ?mls commands, i see every ?mls qos command except 
the cos 5 which is assigned to q1 t1. ?Is my approach is correct in dealing 
this question correctly?? does it matter whether we assign cos values to t1 or 
t2 or t3 in the queues???

your input is much appreciated.

thank you
krishna.




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