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New Member

does marking QOS with dscp vlaue without applying will make affect ???

hi all ,

i have topology simple as below :

-------R2--------R1-------INTERNET

i want to ask about very important issue :

ive made marking to my traffic with dscp vlaues on R1 ,

but

i didnt use any applying to QOS on R2

i mean i just made a policy map and applied it on R1 interface towrads internet .

thats only wt i did

the question is :

does marking traffic with dscp vlaues may affect the quality even i didnt  use policy map on R2 that match  these dscp vlause ???

wish to help

here is a sample  , i applied it an interface of  R1 toward the internet as direction (IN)

===================================================

Policy Map LLQX

    Class YOUTUBE

      set ip dscp af43

    Class FACEBOOKVIDEOS

      set ip dscp af33

    Class HTTP

      set dscp af23

    Class DNSQOS

      set dscp af13

    Class class-default

      set ip dscp af11

=====================================================

why im asking that  is :

because

i found a bad internet quality  after the marking even i didnt match these vlause and didnt apply any policies to it

when i removed the policymap that marks the traffic , i found it better !!!!!

wish to help me

regards

7 REPLIES

Re: does marking QOS with dscp vlaue without applying will make

Hello
Sounds like you have inadvertently applied dscp values that are not complying with your ISP's QOS sla -Even though youve posted the policy map it doesn't show what you are classifying in the class maps themselves -only can go by the class map name.

However before you start applying any qos on egress traffic towards your ISP I would suggest to consult them first on what QOS policy's if any they use- most probably they would rewrite all you traffic anyway as it enters their network but it would cost nothing to query them and save you heartache in the long run.


Res
Paul

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does marking QOS with dscp vlaue without applying will make aff

Hi,

as you are saying "... i applied it an interface of  R1 toward the internet as direction (IN)",

do you mean you are marking the traffic incoming from the Internet?

And forwarding it to R2 while some users behind R2 are complaining worse Internet traffic quality?

What do they complain exactly?

And as Paul asked: What are you matching in your class-maps?

Is there any line overloaded between R1 and the users?

And any other device where QoS  could apply? Like Cisco switch, e.g.?

Best regards,

Milan

New Member

Re: does marking QOS with dscp vlaue without applying will make

Hi mr Milan u r right about every thing ,
There is congestion in link between R1,R2 at rush hour ,

But on R2 I've applied LLQ and it's fine , I don't match any disco values from others ,I mean that R2 is doing every thing in qos.

I found that intrnet was bad ,
When I removed the marking from R1 , I found it better.

My question again ,
Does marking packets without doing any thing in that traffic will make affect ,especially when there is rush hour and congestion ?

I have be from ISP allowed is 750 MBPS, that's why when 750mbps full , the congestion occurs


Wish to clarify
Regards

Sent from Cisco Technical Support iPhone App

Re: does marking QOS with dscp vlaue without applying will make

Hi,

are you sure you are not matching the DCSP values anywhere?

On R2 or R1 (outgoing interface towards R2)?

What kind of interface is used between R1 and R2 (serial or Ethernet?)

What is the router model and IOS version?

Isn't the router CPU overloaded?

Best regards,

Milan

New Member

Re: does marking QOS with dscp vlaue without applying will make




are you sure you are not matching the DCSP values anywhere?
On R2 or R1 (outgoing interface towards R2)?

What kind of interface is used between R1 and R2 (serial or Ethernet?)
What is the router model and IOS version?
Isn't the router CPU overloaded?

Best regards,
Milan
=================
Hi Milan
Thanks a lot
Yes I'm sure that I'm not matching these dscp values anywhere

About CPU when using LLQ is 85 %

I'm using router 7200 with iOS 12.4(12.r)T

Link between routers is giga Ethernet

Regards

Sent from Cisco Technical Support iPhone App

Re: does marking QOS with dscp vlaue without applying will make

Hi,

I'm afraid 750 Mbps could be quite enough for 7200 router?

See http://www.cisco.com/web/partners/downloads/765/tools/quickreference/routerperformance.pdf

And CPU load 85% is also a quite high number.

What's the CPU load difference when you remove the LLQ from your config?

If it makes a big difference, it might be also interesting to mark only some traffic (remove Class HTTP and class-default from your Policy Map LLQX, e.g.) and observe if it makes any difference.

Best regards,

Milan

New Member

Re: does marking QOS with dscp vlaue without applying will make

Hi Milan ,thanks a lot

CPU drop to 55 when remove LLQ

,that's why I want to do mark on R1 and march these marks by R2

If I did it ,
The CPU will go down to 55%
R1 is cisco 7604 and when I use marking on it ,the CPU don't affect

also ,7604 don't support LLQ neither cbwfq
But it can mark

Again
I don't want go far
Does mRking without using these dscp values mY do problems ?

Regards


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