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VOIP QOS on VXR 7206

I am trying to get VOIP setup on a 7206vxr router on the edge of a network to accept dscp markings brought in from a switch and give them priority out the WAN.

Basically I have 13 sites in a ring coming to an edge router.  Each router is taking a voip dscp marking of 40 and giving it a priority of 3 that will come to the central location and I want to be able to see the different packets moving in queue.  Here is my config and I am new to this so if my thinking is wrong, please let me know and maybe some configuration examples.

My g3/0 has sub interfaces on them


!
class-map match-any AutoQoS-VoIP-RTP-Trust
  match ip dscp ef
class-map match-all going-pc
  match access-group 121
class-map match-any AutoQoS-VoIP-Control-Trust
  match ip dscp cs3
  match ip dscp cs5
class-map match-all bla
  match ip rtp 16384 16383
!
!
policy-map AutoQos-Policy-Trust
  class AutoQoS-VoIP-RTP-Trust
   bandwidth percent 5
  class AutoQoS-VoIP-Control-Trust
   bandwidth percent 5
  class class-default
   fair-queue
!
!
interface GigabitEthernet3/0
 no ip address
 service-policy output AutoQos-Policy-Trust
 negotiation auto
!

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cstallings
Asked:
cstallings
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1 Solution
 
Brain2000Commented:
class-map match-any AutoQoS-VoIP-Control-Trust
  match ip dscp 40
!
policy-map SetPriority
  class AutoQoS-VoIP-RTP-Trust
    set ip dscp cs3
!
interface GigabitEthernet2/0  *** set your input interface, I used 2/0 as an example ***
  service-policy input SetPriority
!
interface GigabitEthernet3/0
  service-policy output AutoQos-Policy-Trust
!

It looks like RTP (voice) is marked with priority dscp ef, and the control channel is marked with cs5 (40), but you want to remark it as cs3.  By setting an input policy on the incoming GE, it should be able to mark it.

I also notice that you are allocating only 5% of a gigabit port for voice.  Make sure that if the gigabit line hits 90% or more usage that the voice will even make it through your network.

I might also do something like this:

policy-map AutoQos-Policy-Trust
  class AutoQoS-VoIP-RTP-Trust
   priority percent 10
  class AutoQoS-VoIP-Control-Trust
   bandwidth percent 5
  class class-default
   fair-queue
!

That will give voice traffic the upmost priority going out.  But beware, if you go past 100MBits of voice traffic, the priority statement will begin to rate limit.  But 100MBits is over 1,500 G711 voice calls!
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Brain2000Commented:
You also mentioned that GE3/0 has subinterfaces.  By applying the service-policy on the main interface, all the subinterfaces will fall under that policy.  However, if you need to limit different VLAN's, then you'll need to spply policies to each GE3/0 subinterface instead of the main interface.
0
 
Brain2000Commented:
Ack, I typod.  Why can't you edit your posts in EE?

class-map match-any AutoQoS-VoIP-Control-Trust
  match ip dscp cs5
!
policy-map SetPriority
  class AutoQoS-VoIP-Control-Trust
    set ip dscp cs3
!

I was setting your RTP traffic to cs3 instead of control traffic.  Also, I just confirmed that dscp 40 is cs5.
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cstallingsAuthor Commented:
Well let me ask you this, the uplink from the internetcloud will be a 50X50 connections, so 5% would be enough? or should I go 10?  Does this mean that if I do 10 or whatever number, that is allocated out of the pool for upload or would that only become an issue if the pipe is maxed out?

As far as the markings, the backbone from site to site in the backhauls are accepting dscp 40 from the router and marking it as priority 3 back to the router that I want to setup to go out.

for sake of help, my outgoing connection to realworld is fe0/0 and I have fiber going to my network via g3/0 with subinterfaces 0.11, 0.12, 0.13, 0.14.  I am not concerned with vlan priority on this with the vlans
0
 
Brain2000Commented:
Let me ask you a quick question before I post another config snippet.  By 50X50, are you saying that your internet is 50MBits up and 50MBits down?
0
 
cstallingsAuthor Commented:
Sorry took so long, yes that is correct 50megs by 50 megs
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Brain2000Commented:
Ahh, that makes sense.  I'm going to switch the service policies around a bit.  I'm going to assume the gigabit will be fast enough to handle voice.

class-map match-any AutoQoS-VoIP-Control-Trust
  match ip dscp cs5
!
policy-map SetPriority
  class AutoQoS-VoIP-Control-Trust
    set ip dscp cs3
!
policy-map AutoQos-Policy-Trust
  class AutoQoS-VoIP-RTP-Trust
   priority percent 50
  class AutoQoS-VoIP-Control-Trust
   bandwidth percent 5
  class class-default
   fair-queue
   random-detect dscp-based
!
policy-map SHAPE50
  class class-default
   shape average 49000000
   service-policy AutoQos-Policy-Trust
!
interface FastEthernet0/0
  service-policy input SetPriority
  service-policy output SHAPE50
!
interface GigabitEthernet3/0
  service-policy input SetPriority
!

I set the percent to 50%.  That might be a tad high, but since using the priority statement can act as a rate-limiter, and voice will be the most important thing you send through this line.

Also, I set the shaper to 49MBits instead of 50.  That way the line can't be max'd out and your ISP start rate limiting your line for you.  It might help if someone is utilizing all 50MBits, and you're trying to just get one call through.  It'll keep you at 49MBits.
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