QOS Lecture 10 Implementing AutoQOS 2006 Cisco Systems

QOS Lecture 10 – Implementing Auto-QOS © 2006 Cisco Systems, Inc. All rights reserved.

Enterprise Qo. S Challenges § Enterprise networks work with new traffic types: IP telephony spreads quickly and requires Qo. S. Mission-critical applications need guaranteed bandwidth. § Qo. S implementation requires significant “challenging” knowledge: Simple networks require a simple Qo. S solution that works instantly. Qo. S deployment should be cheaper and faster. © 2006 Cisco Systems, Inc. All rights reserved.

Cisco Auto. Qo. S: Automating the Delivery of Network Qo. S § Cisco Auto. Qo. S—Qo. S for voice, video, and data: Uses Cisco IOS built-in intelligence to automate Qo. S delivery for most common business scenarios Protects business-critical data applications in the enterprise Simplifies Qo. S deployment for real-time traffic Reduces configuration errors Makes Qo. S deployments simpler, cheaper, and faster Follows Diff. Serv model and other standards in Qo. S Allows customers to retain complete control over their Qo. S configuration © 2006 Cisco Systems, Inc. All rights reserved.

Cisco Auto. Qo. S: Automating the Key Elements of Qo. S Deployment Application classification: Discovers applications and provides appropriate Qo. S treatment Policy generation: Autogenerates initial and ongoing Qo. S policies Configuration: Provides high-level business knobs, and automates Qo. S in multidevice domain Monitoring and reporting: Generates intelligent, automatic alerts and summary reports Consistency: Enables automatic, seamless interoperability among all Qo. S features and parameters © 2006 Cisco Systems, Inc. All rights reserved.

Manual Qo. S Configuration Compared to Auto. Qo. S Configuration Manual Qo. S interface Multilink 1 ip address 10. 1. 61. 1 255. 0 ip tcp header-compression iphc-format load-interval 30 service-policy output Qo. S-Policy ppp multilink fragment-delay 10 ppp multilink interleave multilink-group 1 ip rtp header-compression iphc-format ! REMAINING 34 LINES LEFT OUT Auto. Qo. S interface Serial 0 bandwidth 256 ip address 10. 1. 61. 1 255. 0 autoqos voip © 2006 Cisco Systems, Inc. All rights reserved.

Cisco Auto. Qo. S Evolution § Cisco Auto. Qo. S Vo. IP: First phase addressed IP telephony. One command provisions all basic Qo. S required. Support is provided across broad range of platforms (switches and routers). § Cisco Auto. Qo. S for the Enterprise: Second phase extends capabilities (routers only) for data, voice, and video. Two Qo. S deployment stages: Discovers traffic types, load, and generates policy (NBAR) Implements the generated policy © 2006 Cisco Systems, Inc. All rights reserved.

Configuring Cisco Auto. Qo. S: Router Prerequisites § It cannot be configured if a Qo. S policy (service policy) is attached to the interface. § CEF must be enabled at the interface or ATM PVC. § It classifies an interface as low speed (less than or equal to 768 kbps) or high speed (more than 768 kbps): Correct bandwidth must be configured on all interfaces. If low speed, an IP address must be configured on the interface. © 2006 Cisco Systems, Inc. All rights reserved.

Comprehensive Qo. S Deployment in Two Phases § Phase 1: Run Auto Discovery to profile traffic: Collects data from the offered traffic for several days or weeks as desired Uses NBAR-based protocol discovery Performs statistical analysis § Phase 2: Generate and deploy MQC-based Qo. S policies: Maps applications to their corresponding Diff. Serv classes Assigns appropriate values for bandwidth and scheduling parameters © 2006 Cisco Systems, Inc. All rights reserved.

Phase 1: Traffic Profiling on Routers with Auto Discovery router(config-if)# Trust Boundary DSCP-Marked Packets Traffic Classification and DSCP Marking (NBAR, ACLs, MQC Policy) auto discovery qos [trust] § Process begins discovering and collecting data for Cisco Auto. Qo. S for Enterprise only. § Auto Discovery is enabled on the interface of interest. § Optional trust keyword is used to trust (rely on) the DSCP markings; if unspecified, NBAR will be used. § Default value is untrusted. § Auto Discovery results can be seen with the show auto discovery qos command. © 2006 Cisco Systems, Inc. All rights reserved.

Enabling Auto Discovery Example interface Serial 4/0 point-to-point Encapsulation frame-relay Bandwidth 256 Specify bandwidth, IP address and FR DLCI Ip address 10. 1. 71. 1 255. 0 Frame-relay interface-dlci 100 auto discovery qos Frame Relay © 2006 Cisco Systems, Inc. All rights reserved. Enable Auto Discovery §Auto Discovery: –Command should be enabled on interface of interest. –Do not change interface bandwidth when running Auto Discovery. –Cisco Express Forwarding must be enabled. –All previously attached Qo. S policies must be removed from the interface.

Reviewing the Auto Discovery Generated Qo. S Policy Statistics show auto discovery qos Frame Relay © 2006 Cisco Systems, Inc. All rights reserved. Auto. Qo. S Discovery enabled for applications Discovery up time: 2 days, 55 minutes Auto. Qo. S Class information: Class Vo. IP: Recommended Minimum Bandwidth: 517 Kbps/50% (Peak. Rate) Detected applications and data: Application/ Average. Rate Peak. Rate Total Protocol (kbps/%) (bytes) rtp audio 76/7 517/50 703104 Class Interactive Video: Recommended Minimum Bandwidth: 24 Kbps/2% (Average. Rate) Detected applications and data: Application/ Average. Rate Peak. Rate Total Protocol (kbps/%) (bytes) rtp video 24/2 5337/52 704574 Class Transactional: Recommended Minimum Bandwidth: 0 Kbps/0% (Average. Rate) Detected applications and data: Application/ Average. Rate Peak. Rate Total Protocol (kbps/%) (bytes) citrix 36/3 74/7 30212 sqlnet 12/1 7/<1 1540

Phase 2: Configuring Qo. S Policies on Routers router(config-if)# auto qos [voip [trust] [fr-atm]] § It generates and installs the Qo. S policy based on the Auto Discovery results (Auto. Qo. S for Enterprise). Frame Relay § The optional voip keyword configures Cisco Auto. Qo. S Vo. IP. § Optional trust keyword is used to trust (rely on) the DSCP markings for Vo. IP classification; if unspecified, NBAR will be used. § Default value is untrusted. § Optional fr-atm keyword enables Cisco Auto. Qo. S Vo. IP for the low-speed Frame Relay-to-ATM links. © 2006 Cisco Systems, Inc. All rights reserved.

Cisco Auto. Qo. S for Enterprise: Router Configuration Example 2. Enable Auto Discovery © 2006 Cisco Systems, Inc. All rights reserved.

Configuring Cisco Auto. Qo. S for the Enterprise on a High-Speed Serial Interface § § § § Router>enable Router#configure terminal Router(config)#interface serial 1/2 Router(config)# ip address 10. 100. 1 255. 0 Router(config-if)#bandwidth 1544 Router(config-if)#auto discovery qos Router(config-if)#end Router# Leave Cisco Auto Discovery running, preferably for several days. Router#configure terminal Router(config)#interface serial 1/2 Router(config-if)#auto qos Router(config-if)#exit © 2006 Cisco Systems, Inc. All rights reserved.

Deploying Cisco Auto. Qo. S Vo. IP on Switches § Commands at the interface level configure Cisco Auto. Qo. S Vo. IP: Support for Cisco IP phone and Cisco Soft. Phone Support for Cisco Soft. Phone currently on Cisco Catalyst 6500 Series Trust boundary disabled when Cisco IP phone is moved § Buffer allocation and egress queuing depend on interface type (Gigabit Ethernet or Fast Ethernet). § It is supported on static, dynamic-access, voice VLAN access, and trunk ports. § CDP must be enabled for Cisco Auto. Qo. S Vo. IP to function properly. © 2006 Cisco Systems, Inc. All rights reserved.

Configuring Cisco Auto. Qo. S on Cisco Catalyst 2960 (EI) and 3560 Switches switch(config-if)# auto qos voip trust § Used for trusted connections § Used to trust the ingress Vo. IP packet marking § Use if the uplink is connected to a trusted switch or router only switch(config-if)# auto qos voip cisco-phone § Used for Cisco IP Phone connections § Enables the trusted boundary feature § Uses CDP to detect the presence or absence of a Cisco IP Phone § Qo. S markings of incoming packets are trusted only when the Cisco IP phone is detected © 2006 Cisco Systems, Inc. All rights reserved.

Cisco Auto. Qo. S Vo. IP Switch Configuration Example Auto Discovery notes: • Command should be enabled on the interface of interest. • Do not change interface bandwidth when running Auto Discovery. • Cisco Express Forwarding must be enabled. • All previously attached Qo. S policies must be removed from the interface. © 2006 Cisco Systems, Inc. All rights reserved.

How to Verify Cisco Auto. Qo. S on Routers and Switches Routers Switches P r o c e d u r e E Examine Auto Discovery results: n show auto discovery qos t Examine Cisco Auto. Qo. S templates and initial configuration: F l o w e show auto qos o Explore interface statistics for autogenerated policy: Explore interface-level autogenerated Qo. S parameters: r I show policy-map interface i P r V p s Examine Co. S-to-DSCP maps: show mls qos maps e © 2006 Cisco Systems, Inc. All rights reserved.

Monitoring Cisco Auto. Qo. S on a Router: Step 1 router# show auto discovery qos [interface type]] § Displays the results of the data collected during the Auto Discovery phase for a specific interface or all interfaces router#show auto discovery qos Serial 2/1. 1 Auto. Qo. S Discovery enabled for applications Discovery up time: 2 hours, 42 minutes Auto. Qo. S Class information: Class Voice: Recommended Minimum Bandwidth: 517 Kbps/50% (Peak. Rate). Detected applications and data: Application/ Average. Rate Peak. Rate Protocol (kbps/%) --------------rtp audio 2/<1 517/50 <. . . rest of the output deleted. . . > © 2006 Cisco Systems, Inc. All rights reserved. Total (bytes) -------703104

Monitoring Cisco Auto. Qo. S on a Router: Step 2 router# show auto qos [interface type] § Displays the Cisco Auto. Qo. S templates (policy maps, class maps, and ACLs) created for a specific interface or all interfaces router#show auto qos ! policy-map Auto. Qo. S-Policy-Se 2/1. 1 class Auto. Qo. S-Voice-Se 2/1. 1 priority percent 70 set dscp ef class Auto. Qo. S-Inter-Video-Se 2/1. 1 bandwidth remaining percent 10 set dscp af 41 class Auto. Qo. S-Stream-Video-Se 2/1. 1 bandwidth remaining percent 5 set dscp cs 4 class Auto. Qo. S-Transactional-Se 2/1. 1 bandwidth remaining percent 5 <. . . rest of the output deleted. . . > © 2006 Cisco Systems, Inc. All rights reserved.

Monitoring Cisco Auto. Qo. S on a Router: Step 3 router# show policy-map interface [interface type] § Displays the packet statistics of all classes that are configured for all service policies on the specified interface, subinterface, or PVC router#show policy-map interface Fast. Ethernet 0/0. 1 Service-policy output: voice_traffic Class-map: dscp 46 (match-any) 0 packets, 0 bytes 5 minute offered rate 0 bps, drop rate 0 bps Match: ip dscp 46 0 packets, 0 bytes 5 minute rate 0 bps Traffic Shaping Target Byte Sustain Excess Interval Increment Adapt Rate Limit bits/int (ms) (bytes) Active 2500 10000 333 1250 <. . . rest of the output deleted. . . > © 2006 Cisco Systems, Inc. All rights reserved.

Monitoring Cisco Auto. Qo. S on a Switch: Step 1 switch# show auto qos [interface-id] § Displays the Cisco Auto. Qo. S Vo. IP configuration that was initially applied § Does not display any user changes to the configuration that might be in effect switch#show auto qos Initial configuration applied by Auto. Qo. S: wrr-queue bandwidth 20 1 80 0 no wrr-queue cos-map wrr-queue cos 1 0 1 2 4 wrr-queue cos 3 3 6 7 wrr-queue cos 4 5 mls qos map cos-dscp 0 8 16 26 32 46 48 56 ! interface Fast. Ethernet 0/3 mls qos trust device cisco-phone mls qos trust cos © 2006 Cisco Systems, Inc. All rights reserved.

Monitoring Cisco Auto. Qo. S on a Switch: Step 2 switch# show mls qos interface [interface-id | vlan-id] [buffers | policers | queueing | statistics] § Displays Qo. S information at the interface level switch#show mls qos Ingress dscp: incoming 1 : 0 Others: 203216935 no_change 0 24234242 classified 0 178982693 Egress dscp: incoming 1 : 0 no_change n/a classified n/a WRED drop qid 1 : 2 : counts: thresh 1 0 0 interface gigabitethernet 0/1 statistics thresh 2 0 0 Free. Q 1024 <. . . rest of the output omitted. . . > © 2006 Cisco Systems, Inc. All rights reserved. policed 0 0 policed 0 dropped (in bytes) 0

Monitoring Cisco Auto. Qo. S on a Switch: Step 3 switch# show mls qos maps [cos-dscp | dscp-cos] § Displays the maps that are used to generate an internal DSCP value, to represent the priority of the traffic switch#show mls qos maps dscp-cos Dscp-cos map: dscp: 0 8 10 16 18 24 26 32 34 40 46 48 56 -----------------------cos: 0 1 1 2 2 3 7 4 4 5 5 7 7 © 2006 Cisco Systems, Inc. All rights reserved.

Major Enterprise Qo. S Requirements § Trust boundary definition § Identification of applications, protocols of interest (number of classes), and their Qo. S requirements § Determination of classification options § Determination of traffic-marking options § Determination of queue mechanisms and optimal parameters per class § Definition of port- and interface-specific transport features § Designation of bandwidth efficiency mechanisms for low-speed links § Identification of efficient alarm and eventmonitoring options © 2006 Cisco Systems, Inc. All rights reserved.

Diff. Serv Qo. S Mechanisms Enabled by Cisco Auto. Qo. S § Diff. Serv functions are automated and simplified to expedite deployment of Qo. S features for voice, video, and data. Diff. Serv Function Cisco IOS Qo. S Features Behavior Classification § NBAR and IP precedence § Classifies voice, video, and data traffic based on packet attributes; up to 10 classes § DSCP and Co. S Marking § Class-based marking § Sets Layer 2 and Layer 3 attributes to separate packets into classes Congestion management § Percentage-based LLQ and CBWFQ § Provides EF treatment for voice, AF treatment for video and data, and besteffort treatment as default § WRR Shaping § Class-based shaping or FRTS § Shapes to CIR to prevent bursts and smooth traffic to configured rate Congestion avoidance § WRED § Makes intelligent packet drop decisions to prevent tail drops across multiple TCP sessions Link efficiency § Header compression and link fragmentation and interleaving § Reduces Vo. IP bandwidth requirement and jitter experienced by voice packets © 2006 Cisco Systems, Inc. All rights reserved.

Automated Cisco Auto. Qo. S Diff. Serv Class Provisioning Auto Discovery Cisco Auto Qo. S Policy Application and Protocol-Types Cisco Auto Qo. S Classmaps Match Statements Offered Bit Rate (Average and Peak) Minimum Bandwidth to Class Queues, Scheduling and WRED © 2006 Cisco Systems, Inc. All rights reserved. Traffic Class DSCP Co. S IP routing Interactive voice Interactive video Streaming video Telephony signaling Transactionalinteractive Network management Bulk data Scavenger Best effort CS 6 EF AF 41 CS 4 CS 3 AF 21 6 5 4 4 3 2 CS 2 AF 11 CS 1 0 2 1 1 0

Common Issues with Cisco Auto. Qo. S Issue Solution Cisco Auto. Qo. S generates up to 10 classes, but most enterprise networks deploy 3– 6 classes today. Manual consolidation of similar classes to meet the final number of classes actually needed. Cisco Auto. Qo. S does not adapt to Running Auto Discovery on a changing traffic conditions periodic basis followed by reautomatically. enabling of Cisco Auto. Qo. S does not handle all possible scenarios that may occur and might not fit specific classification or policies. © 2006 Cisco Systems, Inc. All rights reserved. Manual fine-tuning of the configuration generated, adding new matching criteria to fit the specific situation.

Interpreting Generated Cisco Auto. Qo. S Configuration § Generated Cisco Auto. Qo. S configuration is examined using show auto qos command, answering these questions: How many classes were identified (class maps)? Which traffic classification (class map) options were selected? Which traffic marking options were selected (policy maps)? Which queuing mechanisms and parameters were designated (policy maps)? Which other Qo. S mechanisms were appointed per class (policy maps)? Were any traffic parameters suggested? Where was the autogenerated policy applied (interface, DLCI, or PVC)? © 2006 Cisco Systems, Inc. All rights reserved.

How to Interpret the show auto qos Command Output LLQ Class-Based Marking CBWFQ Class-Based Shaping NBAR router#show auto qos ! policy-map Auto. Qo. S-Policy-Se 2/1. 1 class Auto. Qo. S-Voice-Se 2/1. 1 priority percent 50 set dscp ef class Auto. Qo. S-Inter-Video-Se 2/1. 1 Nested Policy Map bandwidth remaining percent 10 (Frame Relay) set dscp af 41 class Auto. Qo. S-Transactional-Se 2/1. 1 bandwidth remaining percent 5 set dscp af 21 <. . . part of the output deleted. . . > ! policy-map Auto. Qo. S-Policy-Se 2/1. 1 -Parent class-default Parent Policy Map shape average 1024000 (Frame Relay) service-policy Auto. Qo. S-Policy-Se 2/1. 1 ! class-map match-any Auto. Qo. S-Voice-Se 2/1. 1 match protocol rtp audio ! Classification class-map match-any Auto. Qo. S-Transactional-Se 2/1. 1 match protocol sqlnet <. . . part of the output deleted. . . > <. . . continues on the next slide. . . > © 2006 Cisco Systems, Inc. All rights reserved.

How to Interpret the show auto qos Command Output (Cont. ) § Monitoring Drops in LLQ Thresholds are activated in RMON alarm table to monitor drops in Voice Class. The default drop threshold is 1 bps. RMON event generated by Auto. Qo. S Rmon event 33333 log trap Auto. Qo. S description “Auto. Qo. S SNMP traps for Voice Drops” owner Auto. Qo. S Rmon alarm 33350 cb. Qo. SCMDDrop. Bit. Rate. 2881. 2991 30 Absolute rising-threshold 1 33333 falling-threshold 0 Owner Auto. Qo. S © 2006 Cisco Systems, Inc. All rights reserved. Frame Relay

How to Interpret the show auto qos Command Output (Cont. ) RMON Traps for Voice Packet Drops rmon event 33333 log trap Auto. Qo. S description "Auto. Qo. S SNMP traps for Voice Drops" owner Auto. Qo. S Serial 2/1. 1: DLCI 58 ! Applying all to the DLCI interface Serial 2/1. 1 point-to-point (or Policy Map to the Serial in Non-Frame Relay) frame-relay interface-dlci 58 class Auto. Qo. S-FR-Serial 2/1 -58 ! map-class frame-relay Auto. Qo. S-FR-Serial 2/1 -58 frame-relay cir 1024000 frame-relay bc 10240 Frame Relay Traffic Parameters frame-relay be 0 frame-relay mincir 1024000 service-policy output Auto. Qo. S-Policy-Se 2/1. 1 -Parent © 2006 Cisco Systems, Inc. All rights reserved.

When Is Manual Modification of Auto. Qo. S Configuration Required? © 2006 Cisco Systems, Inc. All rights reserved.

NBAR and ACL Classification § Cisco Auto. Qo. S uses NBAR and ACLs to generate classifications § Any MQC classification mechanism can manually tune the generated classification: Start the Auto Discovery and review the generated results (or take the active classification if Cisco Auto. Qo. S is already activated). Copy the generated classification and modify it offline. Apply the modified classification to a router. class-map match-any Auto. Qo. S-Voice-Se 2/1. 1 match protocol rtp audio ! class-map match-any Auto. Qo. S-Signaling-Se 2/1. 1 match access-group 101 match protocol rtcp ! class-map match-any Auto. Qo. S-Transactional-Se 2/1. 1 match protocol sqlnet match protocol citrix ! access-list 101 permit tcp any eq 1719 access-list 101 permit tcp any eq 1720 access-list 101 permit udp any eq 2427 access-list 101 permit udp any eq 2428 © 2006 Cisco Systems, Inc. All rights reserved. H. 323 MGCP

MCQ Classification Options router(config-cmap)# match match input-interface-name cos-value [cos-value] ip precedence ip-prec-value [ip-prec. . . ] ip dscp ip-dscp-value [ip-dscp-value. . . ] ip rtp starting-port-number port-range § Besides NBAR and ACLs, these major MQC classification options can be used for tuning. § These classification options can be used in any combination as needed to meet specific classification requirements. © 2006 Cisco Systems, Inc. All rights reserved.