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New Member

QoS and NBAR issue on router 1841

I have two issues with router 1841 and I would be thankful to anyone who can help me to solve them.

Last week I configured 1841 router in PPPoE environment.The goal was to configure QoS on router to give VoIP traffic

priority.I used priority queue in combination with shaping to accomplish this task. Since upload speed is 768kbps,

I shaped traffic in accordance with this value.

How can I verify is qos configuration done well? When I type show policy-map interface fastethernet, cannot see any dropped traffic. 

The router uses NBAR for traffic classification. Ip nbar protocol-discovery is configured on interface but when i type

command show ip nbar protocol-discovery stats bits-rate top-n 10 it gives me output that does not reflect real traffic

on interfaces.There is no good traffic analysis on interface dialer0 and fastethernet0/1, especially in inbound direction.

The router shows real traffic only on fastethernet 0/0 in both directions.

Does nbar option work on dialer interface? What should I configure on router to get it to work?

Version of software on router: Cisco IOS Software, 1841 Software (C1841-ADVSECURITYK9-M), Version 12.4(15)T12.

I attached qos configuration and outputs of some commands.

  • WAN Routing and Switching
New Member

Re: QoS and NBAR issue on router 1841

Let me remind you that Qos will not drop any packet's unless there is a congestion. Also you do not have the prioritize voice policy apply on an interface. You can only apply one policy map per direction per interface. You do have some input traffic on dialer 0. Did you took this capture during bussiness hours?

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