Saturday, October 9, 2010

QOS and the error message " CBWFQ : Not supported on subinterfaces"

Hi Guys,

Pete here, so I am doing some more labs, really focusing on IP-IP-GW interaction and QOS to try and get across the line with that, so here is the first thing I wanted to chat about

CBWFQ : Not supported on subinterfaces

Ever seen that error message before? it happens when you try and apply a QOS policy with either the priority command or the bandwidth command on an interface.

HOWEVER, what I did NOT know, is that you can use hierarchical policy maps when faced with this message, observe the below:

BR1-R2#show policy-map
Policy Map voip
Class voip
priority 20 (%)
Class class-default
fair-queue

Policy Map 512
Class class-default
Average Rate Traffic Shaping
cir 512000 (bps) bc 5120 (bits)
service-policy voip


if you now apply the policy-map 512:


interface Serial0/0/1:0.1 point-to-point
description == FR To HQ
ip address 177.0.101.2 255.255.255.0
snmp trap link-status
frame-relay interface-dlci 101
service-policy output 512
end


You can see that it is accepting the fair-queue:


BR1-R2#show policy-map int serial 0/0/1:0.1

Serial0/0/1:0.1

Service-policy output: 512

Class-map: class-default (match-any)
102 packets, 9309 bytes
5 minute offered rate 1000 bps, drop rate 0 bps
Match: any
Queueing
queue limit 64 packets
(queue depth/total drops/no-buffer drops) 0/0/0
(pkts output/bytes output) 102/7795
shape (average) cir 512000, bc 5120, be 5120
target shape rate 512000
lower bound cir 0, adapt to fecn 0

Service-policy : voip

queue stats for all priority classes:

queue limit 64 packets
(queue depth/total drops/no-buffer drops) 0/0/0
(pkts output/bytes output) 0/0

Class-map: voip (match-all)
0 packets, 0 bytes
5 minute offered rate 0 bps, drop rate 0 bps
Match: protocol rtp
Priority: 20% (102 kbps), burst bytes 2550, b/w exceed drops: 0


Class-map: class-default (match-any)
102 packets, 9309 bytes
5 minute offered rate 1000 bps, drop rate 0 bps
Match: any
Queueing
queue limit 64 packets
(queue depth/total drops/no-buffer drops/flowdrops) 0/0/0/0
(pkts output/bytes output) 102/7795
Fair-queue: per-flow queue limit 16



I hope this helps someone out there!




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