Qos not working or badly configured ?

flier55CCO55 · ‎01-25-2014

Hi eXperts,

I am not able to get working QOS as I expect

Two stations are attached to the same switch and one of them is dedicated to upload

traffic intensive.

The goal is to leave all the bandwith available to this pc where there are no other pc

making traffic on internet, but dinamically reduce bandwith to this pc when some other pc

starts to make internet traffic. Match is done watching to fixed destination ip addresses and specific

protocol "https" > this and only this traffic to this specific ip addresses must be reduced.

All policy-maps are matching but there is something wrong because during intensive upload

if I try to open a simple page from another pc, traffic (for e.g. http navigation) is quite impossible.

This is my configuration :

class-map match-any MidPriority-Out

match dscp af21

class-map match-any Voice-Out

match dscp ef

class-map match-any ExcludeIp

match not access-group 107

class-map match-any TrafficType

match protocol dns

match protocol http

match protocol nntp

match protocol ntp

match protocol netbios

match protocol pop3

match protocol secure-ftp

match protocol secure-http

match protocol secure-pop3

match protocol secure-telnet

match protocol ssh

match protocol telnet

class-map match-all HighPriority-in

match class-map ExcludeIp

match class-map TrafficType

class-map match-all IncludeIp

match protocol secure-http

match access-group 107

class-map match-any MidPriority-in

match protocol pptp

match protocol gre

match protocol ftp

match class-map IncludeIp

class-map match-any Voice-in

match access-group 104

match protocol rtp

class-map match-any HighPriority-Out

match dscp af11

!

policy-map Traffic-Out

class Voice-Out

priority percent 50

class HighPriority-Out

bandwidth percent 20

random-detect

class MidPriority-Out

bandwidth percent 5

random-detect

class class-default

fair-queue

random-detect

policy-map Traffic-In

class Voice-in

set dscp ef

class HighPriority-in

set dscp af11

class MidPriority-in

set dscp af21

!

interface FastEthernet0/0

ip address 192.168.0.10 255.255.255.0

ip nat inside

ip virtual-reassembly

speed auto

service-policy input Traffic-In

!

interface ATM1/0

no ip address

no atm ilmi-keepalive

dsl operating-mode auto

pvc 8/35

encapsulation aal5snap

protocol ppp dialer

dialer pool-member 1

!

interface Virtual-Template1 type tunnel

ip unnumbered Dialer0

ip nat inside

ip virtual-reassembly

tunnel mode ipsec ipv4

tunnel protection ipsec profile XX_XX__X

!

interface Dialer0

bandwidth 360

ip address negotiated

ip access-group 100 in

ip nat outside

ip virtual-reassembly

encapsulation ppp

dialer pool 1

dialer-group 1

ppp pap sent-username XXXXX password XXXXXXXXXXXX

ppp ipcp route default

ppp multilink

ppp multilink fragment delay 20

ppp multilink interleave

service-policy output Traffic-Out

!

access-list 107 permit tcp any host ZZ.CCC.VVV.RRR eq 443

dialer-list 1 protocol ip permit

Hoping that my explanation is good!

Thank you very much!

Federico

Joseph W. Doherty · ‎01-27-2014

It might be helpful if you would also note the device, its IOS version and the physical WAN topology/type.

flier55CCO55 · ‎01-30-2014

Yes, you are right!

Unfortunately I remembered too late.

Anyway :

- router 1751V

- IOS

Cisco IOS Software, C1700 Software (C1700-ADVENTERPRISEK9-M), Version 12.4(25b), RELEASE SOFTWARE (fc1)

- WIC/VIC Slot 1:

Alcatel 20150 ADSL WIC

- ADSL link 7mbit down/ 384 (360 real) up

Thank you so much!

Joseph W. Doherty · ‎01-30-2014

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

Liability Disclaimer

In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

Ok, in a situation like yours, where available bandwidth is less than interface bandwidth, you need to "shape" for your bandwidth cap, otherwise QoS won't engage until the interface congests.

Try adding something like:

policy-map ShapeADSL

class class-default

shape average 300000

service-policy Traffic-Out

interface Dialer0

service-policy output ShapeADSL

PS:

BTW, ADSL often uses PPPoE, which takes 8 bytes from the MTU. If this is the case for you, you could set you MTU to 1492 and use mss-adjust of 1352.

Also BTW, technically you can use AF classes however you like, but higher is usually used for "better". I.e. Your HighPriority traffic would normally be something like DSCP AF3x or AF4x, not AF11.

flier55CCO55 · ‎01-30-2014

Hi, see inline, thanks

JosephDoherty ha scritto:

Posting

Ok, in a situation like yours, where available bandwidth is less than interface bandwidth, you need to "shape" for your bandwidth cap, otherwise QoS won't engage until the interface congests.

> I don't want to shape because I want all available bandwith to the second station while there is no traffic from others. YES, I want the QOS engage only in case of congestion dropping less important traffic first.

Try adding something like:

policy-map ShapeADSL

class class-default

shape average 300000

service-policy Traffic-Out

interface Dialer0

service-policy output ShapeADSL

PS:

BTW, ADSL often uses PPPoE, which takes 8 bytes from the MTU. If this is the case for you, you could set you MTU to 1492 and use mss-adjust of 1352.

> No, my case is PPPoA

Also BTW, technically you can use AF classes however you like, but higher is usually used for "better". I.e. Your HighPriority traffic would normally be something like DSCP AF3x or AF4x, not AF11.

> If I am not wrong : EF (biggest priority)

> AF(1-4)x : same priority against 4 Classes (AF1x, AF2x etc)

> AFx(1-3) : different priority inside Classe and against "drop probability"

> for that reason, you turn on the light because, in my opinion, there was a big error

> here :

policy-map Traffic-Out
class-map match-any Voice-Out
match  dscp ef
class-map match-any HighPriority-Out
match  dscp af11
class-map match-any MidPriority-Out
match  dscp af21
!
!
policy-map Traffic-In
class Voice-in
  set dscp ef
class HighPriority-in
  set dscp af11
class MidPriority-in
  set dscp af21

Basically I created competition between af11 and af21 because they have same

priority and not different drop probability.

So, I changed in this way :

policy-map Traffic-Out

class-map match-any Voice-Out

match dscp ef

class-map match-any HighPriority-Out

match dscp af11

class-map match-any MidPriority-Out

match dscp af13

!

policy-map Traffic-In

class Voice-in

set dscp ef

class HighPriority-in

set dscp af11

class MidPriority-in

set dscp af13

Let you know if changes!

Joseph W. Doherty · ‎01-30-2014

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

Liability Disclaimer

In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

> AF(1-4)x : same priority against 4 Classes (AF1x, AF2x etc)

Yes and no. Strictly speaking, there's no implied difference between AF classes, at least in the RFC that defined AF. However, many AF usage recommendations, including (later) RFCs, suggest "higher" is better than "lower". This is also to align with the prior IP Precedence RFC usage where, for example, IPPrec 4 is "better" than IPPrec 3, so also CS4 and/or AF4x is "better" than CS3 and/or AF3x.

Also if HighPriority is really higher vs. MidPriority, normally it would be in a different (and "better") AF class.

flier55CCO55 · ‎01-30-2014

Hi,

so I changed in this way :

policy-map Traffic-In

class HighPriority-in

no set dscp af11

set dscp af41

policy-map Traffic-Out

class-map match-any HighPriority-Out

no match dscp af11

match dscp af41

Let you know!