For testing purpose you can have policer for 100 MB which will controll the traffic so that it would not go beyond 100 MB here is the sample configuration policy-map LIMIT class class-default police  100000000 interface XXX service-policy out LIMIT show policy-map int XXX  should show the drops if packets go above 100 MBPS. if you have a QoS policy  already then you will  be needing to configure 2 level  parent-child policy ... View more

Create a class-map to match Data Vlan Traffic class-map match vlan << ">> Now create policy-map to mark the traffic policy-map class   ...mark the traffic as needed Now Apply the policy on the interfaces connected to 2911 interface service-policy output Verify: You can look at the output "show policy-map interface " Example: class-map class-vlan match vlan 100 policy-map policy-vlan class class-vlan < > interface gi1/1 service-policy output policy-vlan Support Restrictions to match vlan: The following restrictions apply to the match vlan command: •The match vlan command is supported for IEEE 802.1q and Inter-Switch Link (ISL) VLAN encapsulations only. •As of Cisco IOS Release 12.2(31)SB2, the match vlan command is supported on Cisco 10000 series routers only. Here is the link: http://www.cisco.com/en/US/docs/ios/qos/command/reference/qos_m1.html#wp1038903 Another useful link: http://www.cisco.com/en/US/docs/ios/qos/configuration/guide/qos_on_lac_ps6350_TSD_Products_Configuration_Guide_Chapter.html ... View more

Class-map: voice (match-any)         49575139 packets, 10644477652 bytes          5 minute offered rate 0 bps, drop rate 0 bps          Match: access-group 105            49546103 packets, 10638278904 bytes            5 minute rate 0 bps          Match: ip dscp ef (46)            29035 packets, 6198530 bytes            5 minute rate 0 bps          Queueing            Strict Priority            Output Queue: Conversation 264            Bandwidth 500 (kbps) Burst 12500 (Bytes)           (pkts matched/bytes matched) 0/0    <<<<<<<<<<<<-show matches only during congestions which when packets get queued We two packet counters in a class •1)      Packets    Which means the number of packets which match the criteria of the class. This counter increments whether or not the interface is congested. •2)      (pkts matched/bytes matched) 0/0       Which mean the number of packets which match the criteria of the class when the interface was congested. In other words, the interface transmit ring was full, and the driver and the L3 processor system worked together to queue the excess packets in the L3 queues, where the service policy applies. Packets that are process-switched always go through the L3 queuing system and thus increment the "packets matched" counter. At the time this output was taken there is no congestion as the offered rate was 0 , and hence (pkts matched/bytes matched) 0/0 is expected  .as this counter will only increment for processes switched packets or when there is congestion . Here is a good link for reference http://www.cisco.com/en/US/tech/tk543/tk760/technologies_tech_note09186a0080108e2d.shtml ... View more

You have mentioned that you tried FRTS. Can you please confirm what configuration you had. It should have worked with FRTS. if you are not seeing any match  we may need to troubleshoot if the packets coming into the router are marked correctly. Here is the sample config for FRTS ! class-map match-all MEDIA match  dscp ef class-map match-all SIGNALING match  dscp af41 ! ! policy-map VOIP class MEDIA priority percent 50 class SIGNALING priority percent 20 ! ! ! ! ! interface MFR1 no ip address ip route-cache flow load-interval 30 no arp frame-relay frame-relay traffic-shaping   <<<< do this command last ! interface MFR1.501 point-to-point description CONNECTED TO INTERNET ip address 74.10.15.246 255.255.255.252 no arp frame-relay frame-relay interface-dlci 501 IETF   class VOIPovFR        <<<<<<<<<<<<<< ! interface MFR1.502 point-to-point description CONNECTED TO MPLS ip address 74.10.22.26 255.255.255.252 no arp frame-relay frame-relay interface-dlci 502 IETF   class VOIPovFR        <<<<<<<<<<<<<< ! ! map-class frame-relay VOIPovFR no frame-relay adaptive-shaping frame-relay cir 64000    <<<< CIR = MINCIR frame-relay bc 640    <<< bc = CIR / 100 frame-relay be 0 frame-relay mincir 64000  <<<< Change as needed service-policy output VOIP ! please provide show policy-map output. We may have to open TAC case as would be needing interactive/troubleshootingsession. ... View more

Here is the response to the question: srr-queue bandwidth shape 0 0 0 The above command will calculate percentage of bandwidth for queue 1 based on the link speed (But not the interface bandwidth you configure). Eg: config t int gi1/0/1 srr-queue bandwidth shape 10 0 0 0 The bandwidth weight for queue 1 in here is 1/10 == 10% of link speed (i.e. 10% of 1gig = 100Mb) Here is the link which gives more information: http://www.cisco.com/en/US/partner/docs/switches/lan/catalyst3750/software/release/12.2_55_se/commmand/reference/cli3.html#wp1947494 As I understand correctly, You want to rate limit traffic to 100 Mb on gig interface right? Then you can either change the link speed (which you dont want to do) or shape the traffic to 10% of gig interface i.e. "srr-queue bandwidth shape 10 0 0 0" under the interface. Configuring bandwidth 10000 will not help here, interface bandwidth configuration is used for metric calculations in routing protocols. ... View more

The question is not clear to me, I  will  try to answer the best from my interpretation We will be needing to ensure that the traffic leaving the 891 router QoS is configured on the outgoing interface to the central router. class-map match-any voice match access-group name sip-voip ! policy-map QOS class voice priority 2000 class class-default ! policy-map parentQOS class class-default shape average 5000000 service-policy QOS   For central router please let me what kind of connection is it? If it is it Hub and spoke kind of connection. Then on central router we will have config in similar lines.... Step 1: Create class-maps      class-map match-all VIDEO_SIGNAL   match access-group 65   match access-group 165 class-map match-all VOICE_SIGNAL   match access-group 165 class-map match-all CITRIX   match protocol citrix class-map match-all FTP   match protocol ftp class-map match-all VIDEO   match access-group 65 class-map match-any VOICE   match  dscp ef class-map match-all location1   match access-group 161           (create access list to match destination subnets) class-map match-all location2   match access-group 162           (create access list to match destination subnets) class-map match-all location3   match access-group 163           (create access list to match destination subnets) class-map match-all location4   match access-group 164           (create access list to match destination subnets) class-map ================================== Step 2: Create your child policy maps. policy-map LLQ2   class VOICE_SIGNAL    bandwidth percent 2   class VIDEO_SIGNAL    bandwidth percent 3   class VOICE    priority percent 10   class VIDEO    bandwidth percent 20    police 9000000 conform-action transmit  exceed-action drop   class CITRIX    bandwidth percent 25   class FTP    police 5000000 conform-action transmit  exceed-action drop ================================== Step 3: Create the parent policy map. policy-map Parent1 class location1   shape average 3000000              (exmaple shaping value)   service-policy LLQ2 class location2   shape average 1500000                (exmaple shaping value)   service-policy LLQ2 class location3   shape average 1000000                (exmaple shaping value)   service-policy LLQ2 class location4   shape average 750000               (exmaple shaping value)   service-policy LLQ2 ================================== Step 4: Apply map class interface ON WAN interface service-policy output Parent1 If  I have not answered  you question., please provide me the config for 891 and 2911 and the  problem. I will be able to help better. ... View more

1: How does software queue and hardware queue works on WAN links Cisco routers have two types of queues: a hardware queue and a software queue. The hardware queue, which is sometimes referred to as the transmit queue (TxQ), always uses FIFO queuing, and only when the hardware queue is full does the software queue handle packets. Therefore, your queuing configuration only takes effect during periods of interface congestion, when the hardware queue has overflowed. Congestion must occur on the interface first, which causes packets to be held in the TX Ring/TX Queue. When the TX Ring/TX Queue fills, IOS enables the queuing function on the interface Software queue is configured using qos. When there is congestion on the link the software queue will kick it and prioritize the packets and put it in the hardware queue. Depending on the type of interface you have you can configure different type of Qos to implement software queue. 2: What is the reason of output drops on WAN links? How can we minimize them? Output drops are caused by a congested interface. For example, the traffic rate on the outgoing interface cannot accept all packets that should be sent out. The ultimate solution to resolve the problem is to increase the line speed. However, there are ways to prevent, decrease, or control output drops when you do not want to increase the line speed. You can prevent output drops only if output drops are a consequence of short bursts of data. If output drops are caused by a constant high-rate flow, you cannot prevent the drops. However, you can control them; If you see short bursts that fill up the output queue buffer causing output drops, you can increase the hold queue to help with the burst. Router(conf-if)# hold-queue length out This command is only for burst traffic. If you are over congesting the interface you cannot prevent output drops, but you can make sure that priority traffic is not dropped by configuring qos on the interface. This will drop low priority traffic at time of congestion and make sure you priority traffic is not affected. Sometimes it could be a bug where the queues are not getting freed after use and that would need more troubleshooting to isolate and fix in code. 3: What is the function of bandwidth configured on WAN link? Appling a bandwidth statement on a interface does not change the performance of the interface in any way. The main function of using the bandwidth statement is for routing metrics.EIGRP uses the bandwidth of the link set by the bandwidth command when calculating the metrics. ... View more

An Ethernet subinterface is a logical interface in Cisco IOS. You can use the modular QoS command-line interface (CLI) (MQC) to create and apply a service policy to an Ethernet subinterface Cisco IOS logical interfaces do not inherently support a state of congestion and do not support the direct application of a service policy that applies a queueing method. Instead, you first need to apply shaping to the subinterface using either generic traffic shaping (GTS) or class-based shaping you must configure a hierarchical policy with the shape command at the parent level. Use the bandwidth command for CBWFQ, or the priority command for Low Latency Queueing (LLQ) at lower levels. Class-based shaping limits the output rate and (we can assume) leads to a congested state on the logical subinterface. The subinterface than applies "backpressure," and Cisco IOS begins queueing the excess packets that are held by the shaper. Applying a Hierarchical Policy Follow these steps to apply a hierarchical policy: 1.       Create a child or lower-level policy that configures a queueing mechanism. In the example below, we configure LLQ using the priority command and CBWFQ using the bandwidth command.             policy-map child             class voice                     priority 512 2. Create a parent or top-level policy that applies class-based shaping. Apply the child policy as a command under the parent policy since the admission control for the child class is done based on the shaping rate for the parent class.             policy-map parent             class class-default               shape average 2000000        service-policy child 3 Apply the parent policy to the subinterface.         interface ethernet0/0.1 service-policy parent ... View more

Hi Unfortunatley There is no NBAR support on n7k for now and foreseeable future, The 5.2 feature set is documented in the release notes. http://www.cisco.com/en/US/docs/switches/datacenter/sw/5_x/nx-os/release/notes/52_nx-os_release_note.html#wp388984 N7K(config-cmap-qos)# match protocol ? arp       IP ARP bridging  Bridging cdp       Cisco Discovery Protocol clns      ISO CLNS clns_es   ISO CLNS End System clns_is   ISO CLNS Intermediate System dhcp      Dynamic Host Configuration isis      Intermediate System Intermediate System Protocol ldp       Label Distribution Protocol netbios   NetBIOS All the above option if nbar is supported, I would expect to see things like "telnet" "http" "ftp" and the like....something that would require looking at L4 info or using signatures . The work around would be to configure QoS using MQC with ACL etc. Here is the document to configure QoS on Nexus http://www.cisco.com/en/US/docs/switches/datacenter/nexus5000/sw/configuration/guide/cli/QoS.html But please note that this is OUt of scope for the disscussion as it falls in datacenter swicthing domain. Our topic of disscussion is QoS on WAN. I would request you to open a TAC case for more questions on nexus. ... View more

Hello; Please don't grade the questions. Points are being given  before answers. Yes set-dscp-transmit is not available in some switches like on 3560: please see the link below http://www.cisco.com/en/US/docs/switches/lan/catalyst3560/software/release/12.2_35_se/configuration/guide/swqos.html . ... View more

Again we already have points assigned before the question is answered. Please note the grading is for answers not for questions ;-) On switches mostly QoS is implemented in hardware. Some stats cannot be seen in software by commands. For enhancement request I would suggest to open a TAC case. ... View more

Good questions J Here are   some of the things we need to keep in mind while configuring priority •Layer 2 encapsulations are accounted for in the amount of bandwidth specified with the priority command. However, care must be taken to configure a bandwidth that has room for cell tax overhead and possible jitter introduced by the routers in the voice path. •The priority command can be used for Voice over IP (VoIP) on serial links, Frame Relay links, and ATM PVCs. •The priority command cannot be used in conjunction with other policy-map class configuration command, such as the random-detect, queue-limit, and bandwidth commands. •The priority command can be configured in multiple classes, but it should only be used for voice-like, constant bit rate (CBR) traffic. •Configuring the priority command in multiple classes provides the ability to police the priority classes individually. choppy voice: ============ Choppy voice quality is caused by voice packets being either variably delayed or lost in the network. When a voice packet is delayed in reaching its destination, the destination gateway has a loss of real-time information. In this event, the destination gateway must predict what the content of the missed packet can possibly be. The prediction leads to the received voice not having the same characteristics as the transmitted voice. This leads to a received voice that sounds robotic. If a voice packet is delayed beyond the prediction capability of a receiving gateway, the gateway leaves the real-time gap empty. With nothing to fill up that gap at the receiving end, part of the transmitted speech is lost. This results in choppy voice. Many of the choppy voice issues are resolved by making sure that the voice packets are not very delayed (and more than that, not variably delayed). Sometimes, voice activity detection (VAD) adds front-end clipping to a voice conversation. This is another cause of choppy (or clipped) voice ... View more

Hello, Please don't give point before answering questions :-) This look’s like CAT-OS issue.   Please open a TAC case, it could be a bug. Please not that there are no   Bugfixes    available as cat-os   is almost end-of-support. Best regards -Sarala ... View more

The default burst size is calculated for 1/8th of the policed rate of traffic. For example the guaranteed bandwidth of 40,000 bps, it is equal to 8,000 bits or 1,000 bytes. It is  always a good idea to leave the burst size to be calculated by the IOS, which will use the inbuilt algorithm which is approximately 1/8 of the policed rate. also please note there little variation due  card specific burst size changes. The leaky bucket that Traffic Shaping uses has a maximum capacity of Bc plus Be. Hence, the maximum burst allowed is equal to Bc + Be. A sum of tokens equivalent to Bc is added to the token bucket in every Tc time interval. When the router needs to transmit a packet on an exit interface with Traffic Shaping enabled, the packet is transmitted only if there are sufficient tokens in the token bucket. Otherwise, the packet is buffered in the queues set up on the PVC until sufficient tokens are available. In this way, Traffic Shaping ensures that the long-term transmission rate does not exceed the established rate at which tokens are replaced in the bucket and allows the network to manage congestion. Configure Be only if the CIR value is less than the AR.   For voice, Be = 0. ** The token bucket is filled with Bc tokens in each Tc The leaky bucket that Traffic Shaping uses has a maximum capacity of Bc plus Be. Hence, the maximum burst allowed is equal to Bc + Be. A sum of tokens equivalent to Bc is added to the token bucket in every Tc time interval. When the router needs to transmit a packet on an exit interface with Traffic Shaping enabled, the packet is transmitted only if there are sufficient tokens in the token bucket. Otherwise, the packet is buffered in the queues set up on the PVC until sufficient tokens are available. In this way, Traffic Shaping ensures that the long-term transmission rate does not exceed the established rate at which tokens are replaced in the bucket and allows the network to manage congestion. A token bucket is a formal definition of a rate of transfer. It has three components: a burst size, a mean rate, and a time interval (Tc). mean rate = burst size / time interval CIR = Bc / Tc ... View more