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Traffic Shaping on outbound WAN

I have a customer who's outbound interface is a FE interface configured for 100MBs.  The actual circuit is only about 11MB download and just barely 1MB upload.  The policy map they had configured on their interface wasn't being triggered before the link was saturated due to the big difference in interface line speed and the actual circuit bandwidth.  This was causing a problem with their voice services.  I since configure a hiearchal policy-map that is shown below.  I'm just now trying to verify that its working properly or if I have configure it wrong.

Policy Map Wan-Shaping-1MB-Upload
    Class class-default
      Traffic Shaping
         Average Rate Traffic Shaping
         CIR 800000 (bps) Max. Buffers Limit 1000 (Packets)
         Bc 8000 Be 0
      service-policy WAN-OUTBOUND-PMAP

  Policy Map WAN-OUTBOUND-PMAP
    Class MATCH-EF-CMAP
      Strict Priority
      Bandwidth 70 (%)
    Class MATCH-CS3-AF31-CMAP
      Bandwidth 5 (%) Max Threshold 64 (packets)
    Class class-default
      Flow based Fair Queueing
      Bandwidth 0 (kbps)
            exponential weight 9
            explicit congestion notification
            class    min-threshold    max-threshold    mark-probablity
            ----------------------------------------------------------

            0          -                  -                1/10
            1          -                  -                1/10
            2          -                  -                1/10
            3          -                  -                1/10
            4          -                  -                1/10
            5          -                  -                1/10
            6          -                  -                1/10
            7          -                  -                1/10
            rsvp       -                  -                1/10

The above policy map was added to their WAN port fa4.  When I do a sho policy interface fa4, it has consistently shown that shaping is not active (which could just mean that the bandwidth hasn't gotten that high yet)  I was just hoping someone could maybe help me confirm prior to them having problems that this would solve what issue they had.  I've posted the output of the show policy-map interface fa4 for you to look over.  Thanks!

FastEthernet4

  Service-policy output: Wan-Shaping-1MB-Upload

    Class-map: class-default (match-any)
      7961 packets, 925920 bytes
      5 minute offered rate 1000 bps, drop rate 0 bps
      Match: any
      Traffic Shaping
           Target/Average   Byte   Sustain   Excess    Interval  Increment
             Rate           Limit  bits/int  bits/int  (ms)      (bytes)
           800000/800000    1000   8000      0         10        1000

        Adapt  Queue     Packets   Bytes     Packets   Bytes     Shaping
        Active Depth                         Delayed   Delayed   Active
        -      0         7961      925920    11        4091      no

      Service-policy : WAN-OUTBOUND-PMAP

        Class-map: MATCH-EF-CMAP (match-any)
          0 packets, 0 bytes
          5 minute offered rate 0 bps, drop rate 0 bps
          Match: ip dscp ef (46)
            0 packets, 0 bytes
            5 minute rate 0 bps
          Queueing
            Strict Priority
            Output Queue: Conversation 72
            Bandwidth 70 (%)
            Bandwidth 560 (kbps) Burst 14000 (Bytes)
            (pkts matched/bytes matched) 0/0
            (total drops/bytes drops) 0/0

        Class-map: MATCH-CS3-AF31-CMAP (match-any)
          0 packets, 0 bytes
          5 minute offered rate 0 bps, drop rate 0 bps
          Match: ip dscp cs3 (24)
            0 packets, 0 bytes
            5 minute rate 0 bps
          Match: ip dscp af31 (26)
            0 packets, 0 bytes
            5 minute rate 0 bps
          Queueing

              Output Queue: Conversation 73
            Bandwidth 5 (%)
            Bandwidth 40 (kbps)Max Threshold 64 (packets)
            (pkts matched/bytes matched) 0/0
        (depth/total drops/no-buffer drops) 0/0/0

Class-map: class-default (match-any)
          7961 packets, 925920 bytes
          5 minute offered rate 1000 bps, drop rate 0 bps
          Match: any
          Queueing
            Flow Based Fair Queueing
            Maximum Number of Hashed Queues 64
        (total queued/total drops/no-buffer drops) 0/0/0
             exponential weight: 9
             explicit congestion notification

  class    Transmitted      Random drop      Tail drop    Minimum Maximum  Mark
           pkts/bytes       pkts/bytes       pkts/bytes    thresh  thresh  prob
      0    7155/848278          0/0              0/0           20      40  1/10
      1       1/60              0/0              0/0           22      40  1/10
      2       0/0               0/0              0/0           24      40  1/10
      3       0/0               0/0              0/0           26      40  1/10
      4       0/0               0/0              0/0           28      40  1/10
      5       0/0               0/0              0/0           30      40  1/10
      6     394/34960           0/0              0/0           32      40  1/10
      7       0/0               0/0              0/0           34      40  1/10
   rsvp       0/0               0/0              0/0           36      40  1/10


  class     ECN Mark
            pkts/bytes
      0        0/0
      1        0/0
      2        0/0
      3        0/0
      4        0/0
      5        0/0
      6        0/0
      7        0/0
   rsvp        0/0

2 REPLIES
Cisco Employee

Re: Traffic Shaping on outbound WAN

You have queued 11 packets which means that the shaper was active but only for a short duration.

The configs looks good and should shape to 800k with no burst capabilites. having shaped to 80% bandwidth is good as well so shaper will get active just before it hits the roof on the upload limits. If the service provider allows an occasional burst you might want to give a Be value based on that.

Shelley.

Silver

Re: Traffic Shaping on outbound WAN

Hi

As mentioned above, it looks good. You can see in the output that at some point there has been traffic that has been shaped.

   Adapt  Queue     Packets   Bytes     Packets   Bytes     Shaping
        Active Depth                         Delayed   Delayed   Active
        -      0         7961      925920    11        4091      no

this show's that 11 packets have been delayed due to traffic exceeds 800000.

It,s a good idea to have the shaper configured slitly below the providers bandwidth to make room for the layer2 overhead, because the shaper doesn't account for the layer2 overhead,

/Mikael

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