Per Site QOS policy with Cisco IOS-XE

Jason Lester jlester at wcs.k12.va.us
Thu May 9 14:55:19 UTC 2013


We had a similar problem years ago with a frame-relay <---> IMA setup.  The
hub end was a multiplexed ATM circuit with PVC's to each site's frame-relay
circuit.  The IMA speed was equal to the aggregate speed of each site's
CIR.  It worked great until all the sites were bursting above CIR.  VoIP
call quality would go really bad when that happened (early mornings
mainly.)  QoS policies could not be maintained between the frame and ATM
sides.

Sprint (support contract on the CPE) and MCI (circuits) engineers finally
decided to run PPP over the native protocols on each end and then apply QoS
to the PPP sessions.  That fixed the problem.  I am not sure if something
like that is possible in your case or not though as I am not familiar with
MPLS.  I tried to find the config, but I no longer have it.  I remember it
used virtual templates, but don't remember the specifics.

Jason


On Thu, May 9, 2013 at 10:40 AM, Wes Tribble <westribble at gmail.com> wrote:

> Tyler,
>
> Tyler,
>
> I already had a case open with TAC on this issue.  This is what the CCIE
> assigned to the case is saying about that type of policy:
>
>
> Hi Wesley,
>
>
> Yes, I’m afraid that configuration is not possible. We can only mark or
> police traffic on this child policy.
>
>
>
> You will see the following message when trying to attach the service-policy
> to the interface:
>
>
>
> ---
>
> ASR10004(config-if)#service-policy output parent_shaper
> Cannot attach queuing-based child policy to a non-queuing based class
>
> *This is what I sent to her:*
>
>  So this configuration is not possible?
>
> policy-map parent_shaper
>  class class-default
>  shape average 100000000 < --- 100Mbps parent shaper.
>  service-policy site_shaper
>
> policy-map site_shaper
>  class t1_site
>   shape average 1536000
>   service-policy qos_global
>  class multilink_site
>   shape average 3072000
>   service-policy qos_global
>   class class-default
>   service-policy qos_global
>
> policy-map qos_global
>  class VOICE
>   priority percent 25
>   set dscp ef
>  class AF41
>   bandwidth percent 40
>   set dscp af41
>   queue-limit 1024 packets
>  class class-default
>   fair-queue
>   set dscp af21
>   queue-limit 1024 packets
>
> On Thu, May 9, 2013 at 8:33 AM, Tyler Haske <tyler.haske at gmail.com> wrote:
>
> >  Wes,
> >
> > The earlier policy doesn't use bandwidth commands, hence, it doesn't
> > *subscribe* anything. The only thing it does is ensures that individual
> > sites do not exceed their shaped rate. You could add bandwidth statements
> > if you wanted to ensure a certain site always is guaranteed a certain
> > amount of bandwidth from the parent shaper. You can't oversubscribe with
> > the bandwidth command.
> >
> >
> > policy-map parent_shaper
> >  class class-default
> >   shape average 100000000
> >    service-policy site_shaper
> >
> > policy-map site_shaper
> >  class t1_site
> >   shape average 1536000
> >   bandwidth percent 1
> >
> >    service-policy qos_global
> >  class multilink_site
> >   shape average 3072000
> >   bandwidth percent 2
> >    service-policy qos_global
> >  class class-default
> >   bandwidth percent 97
> >    service-policy qos_global
> >
> > policy-map qos_global
> >  ! ... whatever you want here.
> >
> > This would make sure that large sites don't stare out small spoke sites
> > for bandwidth.
> >
> >  On Thu, May 9, 2013 at 8:58 AM, Wes Tribble <westribble at gmail.com>
> wrote:
> >
> >> Thanks for the information Tyler, I will have to play around with that
> >> kind of policy in my lab.  What would you suggest if you are
> >> oversubscribing the interface?  With the child policy inheriting the
> >> bandwith of the parent shaper, wouldn't I run out of bandwidth
> allocation
> >> before I built all the shapers for all of my 29 sites?
> >>
> >
>



-- 

Jason Lester
Administrator for Instructional Technology
Washington County Public Schools
Tel: 276-739-3060
Fax: 276-628-1893
http://www.wcs.k12.va.us


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