4510 QOS issue

[mbrunton77]

I am a seeing QOS issue with our 4510 switches.  When performing a file copy using a Windows client from our NetApp SAN, I am seeing the output drop counter increment when the auto qos policy is applied to the client interface.  The copy will start out, then pause for 20 to 30 seconds at a time, and then continue along.  When the pauses happens, the drop counter is incrementing.  

GigabitEthernet1/25 is up, line protocol is up (connected) 
  Hardware is Gigabit Ethernet Port, address is 6400.f161.2a38 (bia 6400.f161.2a38)
  Description: 5W-097  A
  MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec, 
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 1000Mb/s, link type is auto, media type is 10/100/1000-TX
  input flow-control is off, output flow-control is off
  Auto-MDIX on (operational: on)
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:37, output never, output hang never
  Last clearing of "show interface" counters 2d20h
  Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 34633

I am seeing the traffic drop under the counter Dbl-Drops-Queue-8

Auto QOS policy on 4510
Building configuration...

Current configuration : 733 bytes
!
policy-map AutoQos-VoIP-Input-Cos-Policy
 class AutoQos-VoIP-Bearer-Cos
   set qos-group 46
 class AutoQos-VoIP-Control-Cos
   set qos-group 24
policy-map AutoQos-VoIP-Input-Dscp-Policy
 class AutoQos-VoIP-Bearer-Dscp
   set qos-group 46
 class AutoQos-VoIP-Control-Dscp26
   set qos-group 26
 class AutoQos-VoIP-Control-Dscp24
   set qos-group 24
policy-map AutoQos-VoIP-Output-Policy
 class AutoQos-VoIP-Bearer-QosGroup
   set dscp ef
   set cos 5
    priority
    police cir percent 33
 class AutoQos-VoIP-Control-QosGroup26
   set dscp af31
   set cos 3
    bandwidth remaining percent 5
 class AutoQos-VoIP-Control-QosGroup24
   set dscp cs3
   set cos 3
    bandwidth remaining percent 5
 class class-default
    dbl
!
end

Does anyone know why this would be happening?

[Rajeev Sharma]

Hey,

Can you try enabling flow control in ingress direction and let us know the result.

Regards,

RS.

[mbrunton77]

I enabled flow-control and it made no difference.

[acampbell]

Hi,

Can you share your interface config too

Regards

Alex

[mbrunton77]

interface GigabitEthernet1/25
 description 5W-097  A
 switchport access vlan 143
 switchport mode access
 switchport voice vlan 355
 load-interval 30
 auto qos voip trust
 qos trust device cisco-phone
 service-policy input AutoQos-VoIP-Input-Cos-Policy
 service-policy output AutoQos-VoIP-Output-Policy
end

NY-4510-5W-1#sh policy-map
  Policy Map AutoQos-VoIP-Input-Cos-Policy
    Class AutoQos-VoIP-Bearer-Cos
      set qos-group 46
    Class AutoQos-VoIP-Control-Cos
      set qos-group 24

  Policy Map AutoQos-VoIP-Input-Dscp-Policy
    Class AutoQos-VoIP-Bearer-Dscp
      set qos-group 46
    Class AutoQos-VoIP-Control-Dscp26
      set qos-group 26
    Class AutoQos-VoIP-Control-Dscp24
      set qos-group 24

  Policy Map AutoQos-VoIP-Output-Policy
    Class AutoQos-VoIP-Bearer-QosGroup
      set dscp ef
      set cos 5
      priority
     police cir percent 33
       conform-action transmit
       exceed-action drop
    Class AutoQos-VoIP-Control-QosGroup26
      set dscp af31
      set cos 3
      bandwidth remaining percent 5
    Class AutoQos-VoIP-Control-QosGroup24
      set dscp cs3
      set cos 3
      bandwidth remaining percent 5
    Class class-default

 Service-policy output: AutoQos-VoIP-Output-Policy

    queue stats for all priority classes:
      Queueing
      queue limit 400 packets
      (queue depth/total drops)  0/0
      (bytes output) 107845

    Class-map: AutoQos-VoIP-Bearer-QosGroup (match-all)
      0 packets
      Match: qos-group 46
      QoS Set
        dscp ef
        cos 5
      Priority: Strict, b/w exceed drops: 0
      
      police:
          cir 33 %
          cir 330000000 bps, bc 10312500 bytes
        conformed 0 bytes; actions:
          transmit
        exceeded 0 bytes; actions:
          drop
        conformed 0000 bps, exceed 0000 bps

    Class-map: AutoQos-VoIP-Control-QosGroup26 (match-all)
      0 packets
      Match: qos-group 26
      Queueing
      queue limit 264 packets
      (queue depth/total drops)  0/0
      (bytes output) 0
      QoS Set
        dscp af31
        cos 3
      bandwidth remaining 5%

    Class-map: AutoQos-VoIP-Control-QosGroup24 (match-all)
      3516 packets
      Match: qos-group 24
      Queueing
      queue limit 264 packets
      (queue depth/total drops)  0/0
      (bytes output) 640
      QoS Set
        dscp cs3
        cos 3
      bandwidth remaining 5%

    Class-map: class-default (match-any)
      102355016 packets
      Match: any
        102355016 packets
      
      queue limit 1160 packets
      (queue depth/total drops)  0/0
      (bytes output) 23653743876
      dbl
          Probabilistic Drops: 6 Packets
          Belligerent Flow Drops: 458 Packets

This is what I am seeing.  When I perform a copy from the NetApp to my Windows client, the Belligerent Flow Drop counter increments, which causes pauses and slowness during the copy.  However, if I perform the copy using a Mac, the Belligerent Flow Drops do not increment and copy speed is great.  About 800Mb/s.