Cisco 2621XM Qos/Tos settings 1

[imagefree]

Hi,

I need some help. I am the lone IT guy at a small call centre and I am having call quality issues. My attempt to segregate traffic without VLANs has been adequate but not perfect.
I have a T1 and a 6meg ADSL at my disposal, I've been trying to route all web traffic through the ADSL using NAT policies and firewall restrictions.

My current set up is a Cisco 2600 -> Sonicwall 2400 -> linksys router

The sonicwall has two WAN ports one from the cisco and the other from the adsl. The sonicwall doesnt provide vlans so I've been using load balancing round robin, routing most http traffic through the ADSL.
This is not ideal and I suffer from poor quality even dropped calls.

Ive been told that "bandwidth reservation for voice and TOS priority would be ideal."

The question is. How do you configure a Cisco 2600 router to reserve bandwith for udp traffic up to 90% and 10 % for the tcp?

I would appreciate your help and time.

 

[maheick]

So what you want is a QoS policy that provides priority for your voice traffic, correct?

Mark

 

[imagefree]

Correct!
I dont think the Sonicwall 2400 is utilizing the QoS configurations I have attempted. Not sure if the sonicwall does a good job of picking out sip and giving it the best effort.

I need to implement QoS on the cisco outer. The directions ive found online are kind of vague and not ideal for my network topology

 

[imagefree]

Can someone help me to set up QoS policy on a Cisco 2621xm to give preference to my voip/sip traffic.

I would truly appreciate it.

"bandwidth reservation for voice and TOS priority would be ideal." 90% udp would be great...

 

[Minue]

Hello
You haven't posted enough information,so as to get a good example of a QOS deployment for your network.Are you using cisco ip phones,is voice traffic being mark by some other device in the network?
In any case it would be best to mark on RTP packets and not UDP packets because lot's of traffic types can fall in the UDP class.Below is example config,don't know if it will help much,because lack of bandwith and congestion doesn't seem to be your problem.It looks more link a design issue.
Note: The conf provided is for upstream bandwith,voip traffic will not be prioritize in downstream.

class-map match-any RTP
match match protocol rtp audio

policy-map VOICE
class RTP
priority percent 90


interface fastethernet0/0
service-policy output VOICE


Regards

 

[imagefree]

Thank you for posting a response.
We have 10 Grandstream ip phones. The agents use soft phones (xlite & twinkle). Voip traffic is not being marked. What would be the pest solution for marking the packets?

And I would need priority on both down and upstream.
Thanks in advance.

 

[Minue]

Hello
The example I posted is a good starting point.Try to implement it and let me know how it's going by posting a show policy-map interface.
Try only upstream for now t keep things simple.

Regards

 

[imagefree]

Ok,

I followed your instructions and I have posted the output of the instructions given below:

xxx(config-cmap)#match protocol rtp audio
xxx(config-cmap)#policy-map VOICE
xxx(config-pmap)#class RTP
xxx(config-pmap-c)#priority percent 90
xxx(config-pmap-c)#int f0/0
xxx(config-if)#service-policy output VOICE
I/f FastEthernet0/0 class RTP requested bandwidth 90%, available only 75%
xxx(config-if)#^Z
xxx#
*Mar 3 15:44:22.104: %SYS-5-CONFIG_I: Configured from console by console

But there was no output from the show policy-map interface.

 

[imagefree]

Ok,

I gave it another shot this time putting the percentage to 70.
Here's the output:

router#show policy-map interface fa0/0
FastEthernet0/0

Service-policy output: VOICE

Class-map: RTP (match-any)
0 packets, 0 bytes
5 minute offered rate 0 bps, drop rate 0 bps
Match: protocol rtp audio
0 packets, 0 bytes
5 minute rate 0 bps
Queueing
Strict Priority
Output Queue: Conversation 264
Bandwidth 70 (%)
Bandwidth 70000 (kbps) Burst 1750000 (Bytes)
(pkts matched/bytes matched) 0/0
(total drops/bytes drops) 0/0

Class-map: class-default (match-any)
38 packets, 5469 bytes
5 minute offered rate 0 bps, drop rate 0 bps
Match: any

Why was I unable to set it to 90%.
I will repost the policy-map in the morning when there is heavy traffic.

 

[imagefree]

Here's an output for this morning:

router#show policy-map interface fa0/0
FastEthernet0/0

Service-policy output: VOICE

Class-map: RTP (match-any)
1035601 packets, 77019603 bytes
5 minute offered rate 190000 bps, drop rate 0 bps
Match: protocol rtp audio
1035601 packets, 77019603 bytes
5 minute rate 190000 bps
Queueing
Strict Priority
Output Queue: Conversation 264
Bandwidth 70 (%)
Bandwidth 70000 (kbps) Burst 1750000 (Bytes)
(pkts matched/bytes matched) 12/888
(total drops/bytes drops) 0/0

Class-map: class-default (match-any)
375192 packets, 88210678 bytes
5 minute offered rate 119000 bps, drop rate 0 bps
Match: any

 

[Minue]

Hello
Thanks Burt,I alway forget the default maximum reservable bandwith.
Imagefree you will need to set the bandwith command to your actual contracted speed,for the QoS to work correctly.Your router thinks it has 100Mbps so the QoS will never kick in.After yu have adjust the bandwith,please post another show policy-map interface fa0/0 and a show int fa0/0,so as to see the rx and tx load on the interface.

Regards

 

[imagefree]

Ok, thanks again Minue.
First of all, I'm a rookie to Cisco router configuration.
How do you set the bandwidth command, and would the contracted speed be the speed of the T1?

 

[Minue]

Hello
If I understood your first post correctly,you have two WAN circuits terminating on the Linksys.Is this router load balancing or it's doing some kind of policy based routing(Voip traffic is T1 and data traffic using ADSL)?If neither of the please check to see which WAN is being use for outbound traffic.It very important to know how your traffic is being route to troubleshoot your problem.In any case the command below will set the bandwith:

int fa0/0
bandwith 6000

int fa0/0
bandwith 1544

The above one is for the ADSl and the below for the T1,you will have to decide on the question I ask.Please let me know.

Regards

 

[imagefree]

Ok, I clearly need to redo my network design.

I have two WAN ports. ADSL and T1.
The T1 is ported to s0/0 the fa0/0 to the firewall.
The ADSL is a secondary WAN port on the firewall.

Here's were things get messy.

I have the sonicwall 2400 device configured on load balance round robin, the T1 being the primary WAN interface. I was not able to separate the WAN ips and route all data to ADSL. I tried to route all the http traffic through the ADSL. Some of the http traffic still flows through the T1 not to mention other packets.

My estimation is that if I can preserve the T1 via the cisco to only sip/voice traffic, the ADSL will handle everything else as the secondary WAN interface.

 

[imagefree]

Ok. I set the bandwidth for the fa0/0 to 1544, here are some outputs.

router#show int fa0/0
FastEthernet0/0 is up, line protocol is up
Hardware is AmdFE, address is 0012.7fdb.bea0 (bia 0012.7fdb.bea0)
Internet address is 208.163.49.57/29
MTU 1500 bytes, BW 1544 Kbit, DLY 100 usec,
reliability 255/255, txload 39/255, rxload 5/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s, 100BaseTX/FX
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:03, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/2/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
Available Bandwidth 1088 kilobits/sec
5 minute input rate 33000 bits/sec, 46 packets/sec
5 minute output rate 242000 bits/sec, 353 packets/sec
20933711 packets input, 2057205245 bytes
Received 563 broadcasts, 0 runts, 0 giants, 0 throttles
21 input errors, 0 CRC, 0 frame, 0 overrun, 21 ignored
0 watchdog
0 input packets with dribble condition detected
58763316 packets output, 1754363804 bytes, 0 underruns
0 output errors, 0 collisions, 15 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out

router#show policy-map interface fa0/0
FastEthernet0/0

Service-policy output: VOICE

Class-map: RTP (match-any)
7706 packets, 577194 bytes
5 minute offered rate 19000 bps, drop rate 0 bps
Match: protocol rtp audio
7706 packets, 577194 bytes
5 minute rate 19000 bps
Queueing
Strict Priority
Output Queue: Conversation 264
Bandwidth 70 (kbps) Burst 1750 (Bytes)
(pkts matched/bytes matched) 0/0
(total drops/bytes drops) 0/0

Class-map: class-default (match-any)
591 packets, 501099 bytes
5 minute offered rate 17000 bps, drop rate 0 bps
Match: any

 

[Minue]

Hello
Be patient with me,but I can't understand your design.Can you please explain it as precise as possible.Which device is terminating the T1? Is the Sonicwall terminating the ADSL line?What's the Linksys doing?
Regards

 

[imagefree]

Ok,

Here is a basic illustration:

T1<->Cisco 2621xm <->
Sonicwall NSA 2400<->Linksys<->Other
ADSL <->

Other would be the other network devices and the patch panel switches.

The Sonicwall NSA is acting as a firewall, a router and the DHCP of the agent stations. It has two WAN ports as illustrated above. The T1 is the primary WAN, the secondary is the ADSL. The NSA is configured to use the ADSL when there is no available bandwidth on the T1. I wanted to block/police traffic allowing only sip/voice traffic through the cisco/t1 WAN port. Thus forcing the rest of the traffic through the ADSL.

This Sonicwall model does not have VLAN capabilities, nor does it allow me to configure destination ports. Just primary and secondary WAN ports and various options of load balancing, I am using round robin.

 

[Minue]

Hello
I think we're getting a bit closer.So the router is terminating the T1 line.And one of it's fastethernet interface is plug into the Sonicwall.Then you have a standalone ADSL modem plug into the sonicwall?If so what's the model of this modem?
The load-balancing seems to be the problem.You can try changing your design to make the network more stable.Like letting the Cisco router handle both the T1 and the ADSl.let me know what you think.

Regards

 

[dgrizzard]

The best option I can come up with for your situation is to route the traffic so that all of your voip is utilizing one connection and regular internet traffic is going out the other. I would personally use the T1 since your up/down will be the same.

Another reason for doing this is that you cannot do QoS on inbound traffic. You would need your isp/provider to do this. Most will now-a-days, but it will cost you. Doing it this way limits the type of traffic you are sending (voip only) so you will not need inbound QoS. If you are still having problems after this you need more bandwidth, its that simple.

For planning purposes you need to figure on 33/kbps per simultaneous call. Not necessarily per agent. Via your PBX (if it does this) or your SIP provider try to get a traffic report of your busy hour during the week and use that as a baseline for the amount of bandwidth you will need.

 

[imagefree]

Sorry for the late response. Been very hectic, for those who are a stand alone IT guy you will understand.

Minue thanks again for your help, I truly appreciate it. Your suggestions seems like the best bet. Correct me if I am wrong if I used the Cisco 2621xm for both the ADSL and the T1 I could use similar policies, like the one you gave me, to police voice traffic through the T1 and data through the ADSL?

Currently the 2621xm has one WIC (CSU/DSU)card, and I am sure I will need to install another one in a few months when more bandwidth is needed. That means I will be utilizing both serial ports. I am not familiar with Cisco routers, the 2621xm has a another module port (the wide port), can a ADSL card be purchased for this port?


nikeair,
That is what I am trying to do with my current equipment. I was trying to accomplish this with the Sonicwall 2400. However it seems the Cisco 2621 would be more suitable for this application.
My intention was to block all non-voice traffic from going through the T1 and have it overflow into the ADSL. However this is not working well.