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QOS help and dropped packets

I am trying out a new QOS map and ran into dropped packets on our second site. The first site I implemented this on is working with no packet loss. The second site has two routers and both are randomly dropping packets. All sites are running Cisco 3925 routers with DS3 encap PPP circuits. First site has one router and the other has two routers. The packet loss does not seem to be service affecting, but we shouldn't be seeing any packet loss, as the circuits haven't gone over 20% utilization.

Any comments or suggestions would be greatly appreciated. Below is the config added and show policy-map:

class-map match-any AF4x

match ip dscp af41

class-map match-any AF3x

match ip dscp af31

class-map match-any AF2x

match ip dscp af21

class-map match-any Voice

match ip dscp ef

class-map match-any Scavenger

match ip dscp cs1

class-map match-any AFclass

match ip dscp af21  af31  af41

!

!

policy-map AFsubclass

class AF4x

   police rate percent 20

     exceed-action set-dscp-transmit af42

class AF3x

   police rate percent 5

     exceed-action set-dscp-transmit af32

class AF2x

   police rate percent 5

     exceed-action set-dscp-transmit af22

!

policy-map STDqos

class Voice

  priority percent 10

class AFclass

  bandwidth percent 25

  service-policy AFsubclass

class Scavenger

   police rate percent 4

     exceed-action set-dscp-transmit default

     violate-action drop

class class-default

  bandwidth percent 50

  random-detect dscp-based

!

policy-map Shape

class class-default

  shape average 44210000

  service-policy STDqos

!

interface Serial1/0

service-policy output Shape

!

sh policy-map int s 1/0  | inc Class|offered|drops

    Class-map: class-default (match-any)

      30 second offered rate 5141000 bps, drop rate 0 bps

      (queue depth/total drops/no-buffer drops) 0/123/0

          (queue depth/total drops/no-buffer drops) 0/35/0

        Class-map: Voice (match-any)

          30 second offered rate 4611000 bps, drop rate 0 bps

          Priority: 10% (4421 kbps), burst bytes 110500, b/w exceed drops: 0

        Class-map: AFclass (match-any)

          30 second offered rate 0 bps, drop rate 0 bps

          (queue depth/total drops/no-buffer drops) 0/0/0

            Class-map: AF4x (match-any)

              30 second offered rate 0 bps, drop rate 0 bps

            Class-map: AF3x (match-any)

              30 second offered rate 0 bps, drop rate 0 bps

            Class-map: AF2x (match-any)

              30 second offered rate 0 bps, drop rate 0 bps

            Class-map: class-default (match-any)

              30 second offered rate 0 bps, drop rate 0 bps

        Class-map: Scavenger (match-any)

          30 second offered rate 0 bps, drop rate 0 bps

        Class-map: class-default (match-any)

          30 second offered rate 527000 bps, drop rate 0 bps

          (queue depth/total drops/no-buffer drops) 0/53/0


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QOS help and dropped packets

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It's possible drops are due to microbursts and insufficient queue depths.

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