Getting a wrong DSCP value while configuring QOS settings

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Below is the config on my test environment. I am currently testing with NEC dTerm IP phones and C5K stacks.

Trying to make sure QOS settings are correct and the voice packets have high priority. However, when I trace my packets, I keep getting the DSCP value of 47 (2F) from the phones instead of 46 (2E) like I expect to see.

Could someone let me know where I might be going wrong? Or what I need to be looking at?

Thank you in Advance


#vlan
set vlan create 10
set vlan create 507
set vlan create 1007
set vlan name 10 "Voice"
set vlan name 507 "data"
set vlan name 1007 "Voice"
clear vlan egress 1 ge.1.9;ge.1.17;ge.1.32
set vlan egress 507 ge.1.48 tagged
set vlan egress 507 ge.1.9;ge.1.17;ge.1.32 untagged
set vlan egress 1007 ge.1.1;ge.1.48 tagged
!


#ciscodp
set ciscodp status enable
set ciscodp port vvid 1007 ge.1.1
!

#lldp
set lldp port med-trap enable ge.1.1
set lldp port med-trap enable ge.1.7
set lldp port med-trap enable ge.1.8
set lldp port med-trap enable ge.1.9
set lldp port med-trap enable ge.1.17
set lldp port tx-tlv med-pol ge.1.1
set lldp port tx-tlv med-pol ge.1.7
set lldp port tx-tlv med-pol ge.1.8
set lldp port tx-tlv med-pol ge.1.9
set lldp port tx-tlv med-pol ge.1.17
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.1
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.2
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.3
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.4
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.5
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.6
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.7
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.8
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.9
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.10
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.11
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.12
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.13
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.14
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.15
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.16
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.17
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.18
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.19
set lldp port network-policy voice state enable tag tagged vid 1007 cos 7 dscp 46 ge.1.20
!

#cos state
set cos state enable
!

#cos setting
!

#cos port-config
!

#cos port-resource
!

#cos reference
!

#policy
set policy profile 1 name "Voice" pvid-status enable pvid 1007 cos-status enable cos 7 egress-vlans 1007
set policy port ge.1.1 1 
set policy port ge.1.7 1 
set policy port ge.1.8 1 
!

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Abhishek Potdar

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Posted 4 years ago

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rbrt_weiler

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I honestly do not know anything about Enterasys configurations, but I had a similar issue with Avaya phones and Summit switches lately. In the end the telephony guy told us that he configures which DSCP values the phones should use on the Communication Manager. And if that is configured, the phones will ignore whatever is told them via LLDP.
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Paul Poyant, Employee

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Thanks for that possibility, Robert!

Note that there is a GTAC Support case opened today, with this question.
I expect to update this thread with the answer, when that has been determined.
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Paul Poyant, Employee

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The goal of the exercise changed.

Original goal:
LLDP-configure certain ports so that DSCP 46 advertises to connected IP Phones, and the phones in turn will use DSCP 46 in their transmitted traffic.

Evolved goal:
Policy-configure all ports so that any ingress traffic using UDP Source or Destination port value of 5060 or 5061 will be given Priority 6 and have its DSCP value set to 46.

The suggested - but ultimately unconfirmed as to result - configuration to accomplish this...

set policy profile name VoIP cos-status
set policy rule 77 udpdestport 5060 mask 15 cos 8
set policy rule 77 udpsourceport 5060 mask 15 cos 8
set policy port *.*.* 77

set cos state enable
set cos setting 8 priority 6 tos-value 184

This KB article might be helpful as functional background for understanding the suggested configuration:
How To Configure Policy to Mark Voice/video/data with specific Markings on Securestack and S-Series.
(Edited)