Solved: QoS in subinterface

Haris P · ‎05-23-2010

Dears ,

one of my customer is connected through a dot1 Q subinterface on our router , Is there is any way to implement this SLA for his service

policy-map WAN-QoS

class http

priority 3000

set dscp af11

class Mail

bandwidth 2000

set dscp af41

class class-default

fair-queue

Regards

haris

Nagendra Kumar Nainar · ‎05-24-2010

Hi Haris,

The two cases whcih you have mentioned will perform different operations as below,

Case 1:

- HTTP traffic will be shaped to 3 Mbps and will be marked as AF41. HTTP traffic more than 3 Mbps will be buffered and treated with FIFO queueing mechanism by default and if the queue is full, packets will be dropped.

- Mail traffic will be shaped to 1 Mbps and will be marked as AF41.

- Rest all traffic will get WFQ treatment.

Case 2:

- HTTP traffic upto 3 Mbps will be prioritised and will be sent out of the interface first in case there is a congestion.

- Mail traffic will have 2 Mbps even if the interface is congested.

Ay queuing will get kicked in only when it realise that the interface is congested (the hardware queue will be full and the packets will be in software queue). Basically CBWFQ/LLQ (Queuing mechanism) cannot be applied directly on subinterfaces. So you need to configure HQoS where you will first configure a parent policy to shape the traffic as per the CIR of that subinterface and then apply the Queuing policy as child policy.

For example, if you have a subinterface with CIR as 10Mbps and you need HTTP traffic to have 3 Mbps and prioritised always during the time of issue and Mail traffic to have 2 Mbps, you need to configure HQoS as below,

policy-map CHILD

class HTTP

priority 3000

set dscp af11

class Mail

bandwidth 2000

set dscp af41

class class-default

fair-queue

policy-map PARENT

class class-default

shape average 10000000

service-policy CHILD

The above configuration will shape all outbound traffic on this interface to 10 Mbps. Any traffic more than 10 Mbps will be buffered in shaping Queue. By default teh shaping Queue will be FIFO. Now that we have applied a CHILD policy, we made the FIFO queue to LLQ.

HTH,

Nagendra

View solution in original post

Ganesh Hariharan · ‎05-23-2010

Dears ,
one
of my customer is connected through a dot1 Q subinterface on our router
, Is there is any way to implement this SLA for his service 
policy-map WAN-QoS
  class http
   priority 3000
   set dscp af11
  class Mail
   bandwidth 2000
   set dscp af41
  class class-default
   fair-queue
Regards
haris

Hi Haris,

Check out the below link for Qos in sub interface configuration

https://www.cisco.com/en/US/tech/tk543/tk545/technologies_tech_note09186a0080114326.shtml

Hope to Help !!

Ganesh.H

Haris P · ‎05-24-2010

Thanks

The below config. works with me on sub-interface , but what's the difference between this two ? Whether in MQC , if Im not using any bandwith on Mail and class-dfeault whether i will be able to shoot more in HTTP ?

Case1 : MQC

policy-map WAN-QoS
class http
shape average 3072000
set dscp af41
class Mail
shape average 1024000
set dscp af41
class class-default
fair-queue

Case2: CBWFQ

policy-map WAN-QoS

class http

priority 3000

set dscp af11

class Mail

bandwidth 2000

set dscp af41

class class-default

fair-queue

Regards

haris

Nagendra Kumar Nainar · ‎05-24-2010

Hi Haris,

The two cases whcih you have mentioned will perform different operations as below,

Case 1:

- HTTP traffic will be shaped to 3 Mbps and will be marked as AF41. HTTP traffic more than 3 Mbps will be buffered and treated with FIFO queueing mechanism by default and if the queue is full, packets will be dropped.

- Mail traffic will be shaped to 1 Mbps and will be marked as AF41.

- Rest all traffic will get WFQ treatment.

Case 2:

- HTTP traffic upto 3 Mbps will be prioritised and will be sent out of the interface first in case there is a congestion.

- Mail traffic will have 2 Mbps even if the interface is congested.

Ay queuing will get kicked in only when it realise that the interface is congested (the hardware queue will be full and the packets will be in software queue). Basically CBWFQ/LLQ (Queuing mechanism) cannot be applied directly on subinterfaces. So you need to configure HQoS where you will first configure a parent policy to shape the traffic as per the CIR of that subinterface and then apply the Queuing policy as child policy.

For example, if you have a subinterface with CIR as 10Mbps and you need HTTP traffic to have 3 Mbps and prioritised always during the time of issue and Mail traffic to have 2 Mbps, you need to configure HQoS as below,

policy-map CHILD

class HTTP

priority 3000

set dscp af11

class Mail

bandwidth 2000

set dscp af41

class class-default

fair-queue

policy-map PARENT

class class-default

shape average 10000000

service-policy CHILD

The above configuration will shape all outbound traffic on this interface to 10 Mbps. Any traffic more than 10 Mbps will be buffered in shaping Queue. By default teh shaping Queue will be FIFO. Now that we have applied a CHILD policy, we made the FIFO queue to LLQ.

HTH,

Nagendra

Haris P · ‎05-24-2010

Thanks Naikumar,

I solved the problem by putting the LLQ commands under child policy

regards

haris