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Cedric Clark
Cedric Clark used Ask the Experts™
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Backstory:  I did not configure this.  This configuration was already in place for the most part.  The only thing I changed was the priority queue percentages.  The markings were already in place.

The issue here is that when I do packet captures in Wireshark,  I don't see any of the marking

This is the QoS configuration on a 2811 Cisco router:

class-map match-any SDM-Transactional-1
 match dscp af21
 match dscp af22
 match dscp af23
class-map match-any SDM-Signaling-1
 match dscp cs3
 match dscp af31
 match dscp cs2
class-map match-any SDM-Routing-1
 match dscp cs6
class-map match-any SDM-Voice-1
 match dscp ef
 match dscp af43
 match access-group 180
!
policy-map SDM-QoS-Policy-1
 class SDM-Voice-1
  priority percent 60
 class SDM-Signaling-1
  bandwidth percent 15
 class SDM-Routing-1
  bandwidth percent 15
 class SDM-Transactional-1
  bandwidth percent 5
 class class-default
  fair-queue
  random-detect
policy-map SDM-QoS-Policy-3
 class class-default
  shape average 9000000
   service-policy SDM-QoS-Policy-1
policy-map SDM-QoS-Policy-2
 class class-default
  shape average 2944000
   service-policy SDM-QoS-Policy-1

interface Multilink1
 description CenturyLink MPLS -
 ip address x.x.x.x x.x.x.x
 ppp multilink
 ppp multilink interleave
 ppp multilink group 1
 service-policy output SDM-QoS-Policy-2


interface GigabitEthernet0/1
 description Spectrum/Brighthouse Cable
 bandwidth 3072
 ip address x.x.x.x x.x.x.x
 ip access-group INGRESS-FILTER in
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 ip nat outside
 ip inspect SDM_LOW out
 ip virtual-reassembly in
 duplex auto
 speed auto
 no cdp enable
 crypto map mymap
 service-policy output SDM-QoS-Policy-3
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Distinguished Expert 2018

Commented:
Since you are matching traffic according to DSCP there are two choices:
1. that traffic is already previously marked on closer to traffic source
2. router is marking traffic on inbound interface from local network

Capture traffic on ingress interface from inside network is traffic already marked or not.
Check:
- are trunk interfaces on switches configured to trust DSCP/COS marking
- is COS/DSCP mapping configured if needed
- if hosts are marking traffic make sure that access ports trust QoS markings from hosts (not overwriting cos/dscp with zeroes - which is default for ports that are not configured to trust QoS markings)
- if traffic from host is not already marked on hosts, check where and how traffic is marked and that after that all uplinks are trusting QoS marking

Best practice suggests that traffic should be marked as close to source as possible

Author

Commented:
Here is the trunk interface configuration:

interface GigabitEthernet1/0/48
 description Uplink to Cisco 2951
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 1-3
 switchport mode trunk
 srr-queue bandwidth share 1 30 35 5
 priority-queue out
 mls qos trust dscp
 auto qos trust dscp

This is the port configuration closest to the source:

interface GigabitEthernet1/0/7
 switchport mode access
 srr-queue bandwidth share 1 30 35 5
 priority-queue out
 mls qos trust dscp
 auto qos trust dscp
 no cdp enable
 spanning-tree portfast
end

Author

Commented:
I believe that my issue is with one of these interfaces.  This is the uplink interface for the switch that we have at the site.  I don't see any QoS/CoS configurations on them.  

interface GigabitEthernet0/0.1
 description LAN at CAN Clearwater Pharmacy - Clearwater FL
 encapsulation dot1Q 1 native
 ip address x.x.x.x  x.x.x.x
 ip directed-broadcast
 ip nat inside
 ip virtual-reassembly in
end

CANC#sh run int gi0/0
Building configuration...

Current configuration : 99 bytes
!
interface GigabitEthernet0/0
 no ip address
 ip directed-broadcast
 duplex auto
 speed auto
end

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