Applied QOS policy doesnt shape traffic

[Paul Morgan]

Hi all,

I run a basic hierarchical QOS policy on a GRE tunnel interface over an ADSL connection. (Actually we have 30 of them.)

The policy is thus:

Policy-map QOSPOLICY

class VOICE

  percent 40

class CITRIX

  bandwidth 40

class class-default

  fair-queue

Policy-map TUNNEL

class class-default

shape average 350000

service-policy QOSPOLICY

Int tun 0

service-policy output TUNNEL

Very straightforward stuff. Only today, someone managed to get over 600k over the link.

I ran SH INT TUN 0 and saw

" 5 minute output rate 601000 bps "

then I ran SH POLICY-MAP INT TUN 0 and again saw

" 5 minute output rate 601000 bps "

What in the heck is going on? Why hasnt my policy limited the traffic?

[Neeraj Arora]

Shape command in QOS does not drop the traffic till the the time it has queue buffers available to use.

Moreover you are not using any Police command, only the Priority command will police the voice traffic IF it goes beyond 40% of the link. Now it could be possible that traffic other than Voice is eating up the bigger chunk of utilization.

Another thing you can try is configure "bandwidth 350000" on the tunnel 0 interface. That might make a difference

Hope it helps

Neeraj