Cisco Systems OL-4266-08 manual

CH A P T E R 42-1 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 42 Configuring PFC QoS This chapter describes ho w to configur e quality of service (QoS) as implemente d on the Policy Feature Card (PFC) and Distrib uted Forwarding Card s (DFCs) on the Cisco 7600 series routers. Note • For complete sy[...]

42-2 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Understanding How PFC QoS Works Understanding How PFC QoS Works The term “PFC QoS” refers to QoS on the Cisco 7600 series router . PFC QoS is implemented on v arious router components in addition to the PFC and any DF[...]

42-3 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Understanding How PFC QoS Works Figure 42-1 PFC QoS Feat ur e Pr ocessing Overview The PFC QoS features are applied in this order: 1. Ingress port PFC QoS features: – Port trust state—In PFC QoS, trust means to accept[...]

42-4 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Understanding How PFC QoS Works These figur es pro vide more detail about th e rela tionship between QoS and the ro uter components: • Figure 42-2 , T raff ic Flow and PFC QoS Features with PFC3 • Figure 42-3 , T raff[...]

42-5 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Understanding How PFC QoS Works Figure 42-3 sho ws traffic flo w and PFC Qo S features with a PFC2. Figure 42-3 T r affic Flo w and PFC QoS Featur es with PFC2 Figure 42-3 sh ow s ho w traf fic flo ws through the PFC Q oS[...]

42-6 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Understanding How PFC QoS Works Figure 42-4 PFC QoS Featur es an d Component Overview Component Overview These sections pro vide more detail about the role of the f ollo wing components in PFC Qo S decisions and processes[...]

42-7 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Understanding How PFC QoS Works Flowchart of Ingress LAN Port PFC QoS Features Figure 42-5 sh ow s ho w traf fic flo ws through the ing ress LAN port PFC QoS features. Figure 42-5 Ingr ess LAN P ort PFC QoS F eatur es Not[...]

42-8 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Understanding How PFC QoS Works Port Trust In PFC QoS, trust means to accept as valid and use as the basis of the initial inte rnal DSCP value. Y ou can config ure ports as untrusted or you can confi gure them to trust th[...]

42-9 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Understanding How PFC QoS Works Supported Policy Feature Cards The policy feature card (PFC) is a daughter card that resides on the supervisor engine. The PFC pro vides QoS in addition to other functionality . The follo w[...]

42-10 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Understanding How PFC QoS Works Figure 42-6 sh ow s ho w traf fic flo ws through the QoS f eatures on the PFC and DFCs. Figur e 42-6 QoS Featur es on the PFC and DFCs Note The DSCP transparency feature makes writing the [...]

42-11 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Understanding How PFC QoS Works Internal DSCP Values During processing, PFC QoS represent s the priority of all traf f ic (including non-I P traff ic) with an internal DSCP v alue. Initial Internal DSCP Value On the PFC,[...]

42-12 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Understanding How PFC QoS Works Port-Based PFC QoS and VLAN-Bas ed PFC QoS Y ou can conf igure eac h ingress LAN port for either ph ysical port -based PFC QoS (de fault) or VLAN-based PFC Q oS and attach a polic y map to[...]

42-13 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Understanding How PFC QoS Works Flowchart of PFC QoS Egress LAN Port Features Figure 42-7 sh ow s ho w traf fic flo ws through th e QoS features on e gress LAN ports. Figur e 42-7 Egr ess LAN P ort Sc heduling, Cong esti[...]

42-14 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Understanding How PFC QoS Works Egress DSCP Mutation with a PFC3 W ith a PFC3, you can conf igure 15 egress DSCP mutation maps to mutate the internal DSCP valu e before it is written in t he egress T oS byte. Y ou can at[...]

42-15 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Understanding How PFC QoS Works On interfaces where egress A CL support for remarked DSCP is conf igured, the PFC3 processes each QoS-f iltered IP pack et twice: once to appl y ingress PFC QoS and once to ap ply eg ress [...]

42-16 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Understanding How PFC QoS Works Understanding Classification and Marking The follo wing sections d escribe where and ho w classif ication and marking o ccur on the Cisco 7600 series routers: • Classificat ion and Marki[...]

42-17 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Understanding How PFC QoS Works These sections describe classification and marking at trusted ingress ports: • Ingress Classif ication and Marking at T rust CoS LAN Ports, page 42-17 • Ingress Classification and Mark[...]

42-18 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Understanding How PFC QoS Works • T rust CoS (CoS is always zero for POS and A TM OSM ports be cause the port CoS value is not config urable on POS and A TM OSM ports.) Classification and Marking on the PFC Us ing Serv[...]

42-19 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Understanding How PFC QoS Works Classification and Marking on the MSFC PFC QoS send s IP traff ic to the MSF C with the final interna l DSCP values. CoS is equal to IP preceden ce in all tr af fi c sent from the MSFC to [...]

42-20 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Understanding How PFC QoS Works The PFC2 supports only ingress PFC QoS, which includes i ngress policing. Th e PFC3 supports both ingress and e gress PFC QoS, which includes ingress and egress po licing. T raff ic shapin[...]

42-21 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Understanding How PFC QoS Works Microflow Policers PFC QoS applies the bandwidth limit speci fied in a microflo w policer sep arately to each flo w in matched traf f ic. For example, if you conf igure a microflo w po lic[...]

42-22 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Understanding How PFC QoS Works W ith a PFC3, policing uses the Layer 2 frame size. W i th a PFC2, policing uses the Layer 3 packet size. Y ou specify the bandwidth utilizati on limit as a committed information rate (CIR[...]

42-23 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Understanding How PFC QoS Works The Cisco 7600 series router LAN modules support t he follo wing types of scheduli ng algorithms between q ueues: • Shaped round r obin (SRR)—SRR allo ws a queue to use o nly the alloc[...]

42-24 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Understanding How PFC QoS Works Figure 42-10 il lustrates the drop thresho lds for a 1q4t ingress LAN port . Drop thresholds in oth er confi gurations function similarly . Figur e 42-1 0 Receiv e Qu eue Dr op Thresholds [...]

42-25 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Understanding How PFC QoS Works • 1p1q0t indicat es: – One strict-priority queue – One standard queue with no co nfigu rable thre shold (ef fectiv ely a tail-drop threshol d at 100 perce nt). • 1p1q8t indicates t[...]

42-26 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Understanding How PFC QoS Works • 1p7q8t indicates the fo llowing: – One strict-priority queue – Se ven standard queues, each with eight thresholds, each threshold configurable as either WRED-drop or tail-drop Modu[...]

42-27 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Understanding How PFC QoS Works WS-X6324-100FX-MM 1q4t — 2q2t W R R 1 28 KB 16 KB 112 KB WS-X6324-100FX-SM WS-X6348-RJ-45 WS-X6348-RJ-45V WS-X6348-RJ-21V WS-X6224-100FX-MT 64 KB 8 KB 56 KB WS-X6248-RJ-45 WS-X6248-TEL W[...]

42-28 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Default Configuration PFC QoS Default Configuration These sections describe the PFC QoS def ault conf iguration: • PFC QoS Global Settings, page 42-29 • Default V alues W ith PFC QoS Enabled, page 42-30 • D[...]

42-29 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS PFC QoS Default Co nfiguration PFC QoS Global Settings The follo wing global PFC QoS settings apply: Feature Default V alue PFC QoS global enable state Disabled PFC QoS port enable st ate Enabled when PFC QoS is globally[...]

42-30 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Default Configuration Default Values With PFC QoS Enabled These sections list the default values that apply when PFC QoS is enabled: • Receiv e-Queue Limits, page 42-30 • T ransmit-Queue Limit s, page 42-30 ?[...]

42-31 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS PFC QoS Default Co nfiguration Bandwidth Allocation Ratios Default Drop-Threshold Percen tages and CoS Value Mappings The follo wing tables list the def ault drop-thresh old s va lues and CoS mappings for dif ferent queu[...]

42-32 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Default Configuration • 1p2q2t T ransmit Queues, page 42-42 • 1p3q8t T ransmit Queues, page 42-43 • 1p7q4t T ransmit Queues, page 42-44 • 1p7q8t T ransmit Queues, page 42-47 • 1p3q1t T ransmit Queues, p[...]

42-33 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS PFC QoS Default Co nfiguration 1p1q4t Receive Queues 1p1q0t Receive Queues Feature Default V alue Standard receiv e queue T hreshold 1 CoS 0 and 1 T ail-drop 50% WRED-drop Not supported Threshold 2 CoS 2 and 3 T ail-drop[...]

42-34 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Default Configuration 1p1q8t Receive Queues Feature Default V alue Standard receiv e queue Threshold 1 CoS 0 T ail-drop Disabled; 70% WRED-drop Enabled; 40% low , 70% high Threshold 2 CoS 1 T ail-drop Disabled; 7[...]

42-35 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS PFC QoS Default Co nfiguration 1q8t Receive Queues Feature Default V alue Standard receiv e queue Threshold 1 CoS 0 T ail-drop 50% WRED-drop Not supported Threshold 2 CoS None T ail-drop 50% WRED-drop Not supported Thres[...]

42-36 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Default Configuration 2q8t Receive Queues Feature Default V alue Standard receiv e queue 1 (lo w priority) Threshold 1 CoS 0 and 1 T ail-drop 70% WRED-drop Not supported Threshold 2 CoS 2 and 3 T ail-drop 80% WRE[...]

42-37 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS PFC QoS Default Co nfiguration 8q4t Receive Queues Feature Default V alue Standard receiv e queue 1 (lo west priority) Threshold 1 CoS 0 and 1 DSCP 0–9, 11, 13, 15–17, 19, 21, 2 3, 25, 27, 29, 31, 33, 39, 41–4 5, 4[...]

42-38 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Default Configuration Standard receiv e queue 3 (intermediat e priority) Threshold 1 CoS None DSCP 22 T ail-drop Enabled; 100% WRED-drop Disabled; 100% lo w , 100% high Threshold 2 CoS None DSCP 20 T ail-drop Ena[...]

42-39 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS PFC QoS Default Co nfiguration Standard receiv e queue 5 (intermediat e priority) Threshold 1 CoS None DSCP 32, 34–38 T ail-drop Enabled; 100% WRED-drop Disabled; 100% lo w , 100% high Threshold 2 CoS None DSCP None T [...]

42-40 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Default Configuration Standard receiv e queue 7 (intermediat e priority) Threshold 1 CoS None DSCP None T ail-drop Enabled; 100% WRED-drop Disabled; 100% lo w , 100% high Threshold 2 CoS None DSCP None T ail-drop[...]

42-41 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS PFC QoS Default Co nfiguration 8q8t Receive Queues 2q2t Transmit Queues Feature Default V alue Standard receiv e queue 1 (lo west priority) Threshold 1 CoS 0 and 1 T ail-drop Disabled; 70% WRED-drop Enabled; 40% low , 70[...]

42-42 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Default Configuration 1p2q2t Transmit Queues Standard transmit queue 2 (high priority) Threshold 1 CoS 4 and 5 T ail-drop 80% WRED-drop Not supported Threshold 2 CoS 6 and 7 T ail-drop 100% WRED-drop Not supporte[...]

42-43 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS PFC QoS Default Co nfiguration 1p3q8t Transmit Queues Feature Default V alue Standard transmit queue 1 (lo west priority) Threshold 1 CoS 0 T ail-drop Disabled; 70% WRED-drop Enabled; 40% low , 70% high Threshold 2 CoS 1[...]

42-44 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Default Configuration 1p7q4t Transmit Queues Feature Default V alue Standard receiv e queue 1 (lo west priority) Threshold 1 CoS 0 and 1 DSCP 0–9, 11, 13, 15–17, 19, 21, 2 3, 25, 27, 29, 31, 33, 39, 41–4 5,[...]

42-45 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS PFC QoS Default Co nfiguration Standard receiv e queue 3 (intermediat e priority) Threshold 1 CoS None DSCP 22 T ail-drop Disabled; 100% WRED-drop Enabled; 70% low , 100% high Threshold 2 CoS None DSCP 20 T ail-drop Disa[...]

42-46 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Default Configuration Standard receiv e queue 5 (intermediat e priority) Threshold 1 CoS None DSCP 32, 34–38 T ail-drop Enabled; 100% WRED-drop Disabled; 100% lo w , 100% high Threshold 2 CoS None DSCP None T a[...]

42-47 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS PFC QoS Default Co nfiguration 1p7q8t Transmit Queues Standard receiv e queue 7 (intermediat e priority) Threshold 1 CoS None DSCP None T ail-drop Enabled; 100% WRED-drop Disabled; 100% lo w , 100% high Threshold 2 CoS N[...]

42-48 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Default Configuration 1p3q1t Transmit Queues Standard transmit queue 2 (intermediat e priority) Threshold 1 CoS 2 T ail-drop Disabled; 70% WRED-drop Enabled; 40% low , 70% high Threshold 2 CoS 3 and 4 T ail-drop [...]

42-49 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS PFC QoS Configu ration Guidel ines and Restri ctions 1p2q1t Transmit Queues Default Values With PFC QoS Disabled PFC QoS Configuration Guidelines and Restrictions When config uring PFC QoS, follo w th ese guidelines and [...]

42-50 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Configuration Gu id elines and Restrictions General Guidelines • The match ip pr eceden ce and match ip dscp commands fil ter only IPv4 traf f ic. • In Release 12.2(18)SXE and later releases, the match preced[...]

42-51 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS PFC QoS Configu ration Guidel ines and Restri ctions • For these comm ands, PFC QoS applies identical conf iguration to all LAN ports con trolled by the same applic ation-spec ific integrated circuit (A SIC): – rcv-q[...]

42-52 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Configuration Gu id elines and Restrictions • The QoS features implemented in the port ASICs (queue architecture and dequeuing algorithm s) support IPv4 and IPv6 tr aff ic. • The PFC3 supports IPv6 named e xt[...]

42-53 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS PFC QoS Configu ration Guidel ines and Restri ctions Class Map Command Restrictions • W ith Release 12.2(1 8)SXE and later releases, PFC QoS supports the match any cl ass map command. • PFC QoS supports class maps th[...]

42-54 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Configuration Gu id elines and Restrictions W ithin each range, PFC QoS programs the PFC with r ate va lues that are mult iples of the gr anularity va l u e s . Supported Granularity for CIR and PIR Token Bucket [...]

42-55 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS IP Precedence and DSCP Values Configuring PFC QoS These sections describe ho w to conf igure PFC QoS on the Cisco 7600 series routers: • Enabling PFC QoS Globally , page 42-56 • Enabling Ignore Po[...]

42-56 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS • Enabling Microflo w Policing of Bridged T raff ic, page 42-59 • Enabling VLAN-Based PFC QoS on Layer 2 LAN Ports, page 42-60 • Enabling Egress ACL Support for Remarked DSCP , page 42-61 • Cr[...]

42-57 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS IP packets with COS changed by policing: 59998 Non-IP packets with COS changed by policing: 0 Router# Enabling Ignore Port Trust In Release 12.2(18)SXF5 and later releases, the ignore port trust featu[...]

42-58 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS Configuring DSCP Transparency Note • In addition to support for oth er IP traff ic, the PFC3B and PFC3BXL support the no mls qos rewrite ip dscp command for MPLS traff ic, traffic in IP in IP tunnel[...]

42-59 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS Note The router applies the port CoS va lue to untagged ingress traf fic and to traf f ic that is receiv ed through ports th at cannot be conf igured to trust CoS. This exampl e sho ws ho w to enab le[...]

42-60 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS Enabling VLAN-Based PFC QoS on Layer 2 LAN Ports Note • W ith a PFC2, PFC QoS does no t support VLAN-based QoS with DFCs instal led. • W ith a PFC3, PFC QoS supports VLAN-b ased QoS with DFC3s in [...]

42-61 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS Enabling Egress ACL Support for Remarked DSCP T o enab le egress A CL support fo r remarked DSCP o n an ingress in terface, perfor m this task: When config uring egress A CL support for remarked DSCP [...]

42-62 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS When creating a named aggregate pol icer , note the follo wing informat ion: • Aggre gate policing wor ks independently on each DFC-equipped switchin g module and independently on th e PFC, which su[...]

42-63 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS • The v alid range of values for the pir bits_per_secon d parameter is as follo ws: – Minimum—32 kilobits per second, entered as 320 00 (the v alue cannot be smal ler than the CIR bits_per_s eco[...]

42-64 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS Note When you apply both ingress p olicing and e gress polici ng to the same t raf fic, bo th the input pol icy and the output polic y must either mark down traf fic or drop traf fic. PFC QoS does not[...]

42-65 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS PFC QoS Policy Configuration Overview Note T o mark traff ic without limiting bandwidth u tilizat ion, create a policer that uses the transmit ke ywords for both conforming and nonconforming tr af fic[...]

42-66 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS • class-map (optional)—Enter the class-map command to def ine one or mor e traf f ic classes by specifying the criteria by which traf f ic is classified. • policy-map —Enter the pol icy-map co[...]

42-67 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS When config uring protocol-in dependent MA C ACL f iltering, n ote the follo wing informat ion: • Do not conf igure protocol-i ndependent MA C A CL f iltering on VLAN in terfaces where you ha ve con[...]

42-68 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS T o disable VLAN-based QoS f iltering in MA C A CLs, perform this task: Configuring MAC ACLs Y ou can configure named A CLs that filter IPX, DE Cnet, AppleT alk, VINES, or XNS traff ic based on MA C a[...]

42-69 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS • A CL entries are scanned in the order you enter them . The first matchi ng entr y is used. T o improv e performance, place the most common ly used entries near the be ginning of the A CL. • An i[...]

42-70 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS W ith a PFC3 and Release 12.2( 18)SXD and later rele ases, you can configure named ACLs that filter ARP traf f ic (EtherT ype 0x0806) f or QoS. T o configure an ARP A CL for QoS f iltering, perfo rm t[...]

42-71 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS Class Map Filtering Guidelines and Restrictions When configuring class map f iltering, fo llo w these guidelines and restrictions: • W ith Release 12.2(18)SXE an d later releases, PFC Qo S supports [...]

42-72 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS Verifying Class Map Configuration T o verify class map con figur ation, perform this task: This example sho ws ho w to create a class map named ipp5 and how to configure f iltering to ma tch traffi c [...]

42-73 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS This exampl e sho ws ho w to veri fy the conf iguration: Router# show class-map ipp5 Class Map match-all ipp5 (id 1) Match ip precedence 5 Configuring a Policy Map Y ou can attach only one polic y map[...]

42-74 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS Creating a Policy Map Class and Con figuring Filtering T o create a policy map class an d confi gure it to f ilter with a class map, perform t his task: Configuring Policy Map Class Actions When confi[...]

42-75 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS These sections describe polic y map class action conf igurat ion: • Config uring Polic y Map Class Marking, pag e 42-75 • Config uring the Polic y Map Class T rust State, page 42-75 • Config uri[...]

42-76 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS Configuring Policy Map Class Policing When you conf igure polic y map class policing, n ote the follo wing infor mation: • PFC QoS does not support the set- qos-transmit policer ke yword. • PFC Qo[...]

42-77 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS When configuring a per -interface po licer , note the follo wing information: • Aggre gate policing wor ks independently on each DFC-equipped switchin g module and independently on the PFC, wh ich s[...]

42-78 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS Note The flow mask requirements of microflo w policing, NetFlo w , and NetFlo w data e xport (NDE) might confl ict. • The v alid range of va lues for the CIR bits_per_second parameter is as follo ws[...]

42-79 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS • (Optional) F or traf fic tha t excee ds the CIR, you can specify an exceed action as follo ws: – For marking without policing , you can enter the transmit ke yword to transmi t all matched out-o[...]

42-80 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS This exampl e sho ws ho w to veri fy the conf iguration: Router# show policy-map max-pol-ipp5 Policy Map max-pol-ipp5 class ipp5 class ipp5 police flow 10000000 10000 conform-action set-prec-transmit [...]

42-81 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS • Aggre gate policing wor ks independently on each DFC-equipped switchin g module and independently on the PFC, wh ich supports an y non-DFC-equip ped switching modules. Aggre gate policing does not[...]

42-82 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS Configuring Egress DSCP Mutation on a PFC3 Note The PFC2 does not support e gress DSCP mutation. These sections describe ho w to configure e gress DSCP mutation on a PFC3: • Config uring Named DSCP [...]

42-83 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS Note In the DSCP mutation map displays, the mark ed-do wn DSCP v alues are sho wn in the body of the matrix ; the first digit of th e original D SCP value is in the colum n labeled d1 and the secon d [...]

42-84 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS Ingress CoS Mutation Configurati on Guidelines a nd Restrictions When config uring ingress CoS mutation, f ollo w these guidelines and restri ctions: • Release 12.2(17b)SXA and later releases su ppo[...]

42-85 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS Configuring Ingress CoS Mutation Maps T o configure an in gress CoS mutation map, perform th is task: This exampl e sho ws ho w to conf igure a CoS mutation map named testmap: Router# configure termin[...]

42-86 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS This exampl e sho ws ho w to attach the ingr ess Co S mutation map named testma p to Gigabi t Ethernet port 1/1: Router# configure terminal Enter configuration commands, one per line. End with CNTL/Z.[...]

42-87 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS This exampl e sho ws ho w to veri fy the conf iguration: Router# show mls qos maps | begin Cos-dscp map Cos-dscp map: cos: 0 1 2 3 4 5 6 7 ---------------------------------- dscp: 0 1 2 3 4 5 6 7 <[...]

42-88 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS When config uring a DSCP markdo wn map, note the follo wing information: • Y ou can enter the normal-b urst ke yword to conf igure the markdown m ap used by the exceed-action policed-dscp-transm it [...]

42-89 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS Maximum Burst Policed-dscp map: (dscp= d1d2) d1 : d2 0 1 2 3 4 5 6 7 8 9 ------------------------------------- 0 : 00 01 02 03 04 05 06 07 08 09 1 : 10 11 12 13 14 15 16 17 18 19 2 : 20 21 22 23 24 25[...]

42-90 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS This exampl e sho ws ho w to veri fy the conf iguration: Router# show mls qos map | begin Dscp-cos map Dscp-cos map: (dscp= d1d2) d1 : d2 0 1 2 3 4 5 6 7 8 9 ------------------------------------- 0 : [...]

42-91 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS • The mls qos trust cos command enables CoS-based recei ve-queue drop thresholds. T o av oid dropping traf fic because of inconsistent CoS v alues, configure ports with the mls qos trust cos command[...]

42-92 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS T o c onfigure th e CoS value for an ingre ss LAN port, pe rform this task: This exampl e sho ws ho w to configur e the CoS value 5 on Fast Ethernet por t 5/24 and v erify the configuration: Router# c[...]

42-93 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS When you conf igure multiple-t hreshold standard queues, note the fo llo wing information: • The first p ercentage that you enter sets th e lo west-priority threshold. • The second percentage that[...]

42-94 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS This exampl e sho ws ho w to veri fy the conf iguration: Router# show queueing interface gigabitethernet 1/1 | begin Receive queues Receive queues [type = 1p1q4t]: Queue Id Scheduling Num of threshold[...]

42-95 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS T o configure the drop thresholds, p erform this task: Configuring a WRED-Drop a nd Tail-Drop Transmit Queue These port types ha ve bo th WRED-drop and tail-drop th resholds in their transmit qu eues:[...]

42-96 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS This exampl e sho ws ho w to configure the l ow-priority tr ansmit queue high-WRED- drop thresholds for Gigabit Ethernet port 1/1 : Router# configure terminal Enter configuration commands, one per lin[...]

42-97 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS T o co nfigure tail -drop thre shold perc entages for the standard receive an d transmit queues on 1q4t / 2q2t LAN ports, perform this task: When confi guring the recei ve- and transmit-q ueue tail-dr[...]

42-98 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS Mapping QoS Labels to Queues and Drop Thresholds These sections describe ho w to map QoS labels to queues and drop thresholds: Note Enter the show queueing interface { ether net | fastether net | giga[...]

42-99 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS Enabling DSCP-Based Queue Map ping T o enable DSCP-based queue mapping, perform this task: This example shows ho w to enable DSCP-ba sed queue map ping on 10-Gig abit Ethernet po rt 6/1: Router# confi[...]

42-100 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS Router(config)# interface gigabitethernet 6/1 Router(config-if)# mls qos trust dscp Router(config-if)# end Router# This exampl e sho ws ho w to veri fy the conf iguration: Router# show queueing inter[...]

42-101 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS Note The receiv e queue mapping is sho wn in the seco nd “queue thresh dscp-map” displayed b y the show queueing interface command. This exampl e sho ws ho w to veri fy the conf iguration: Router[...]

42-102 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS Mapping DSCP Values to Standard Transmit-Queue Thresholds T o map DSCP values to standard transmit-queue thresholds, p erform this task: When mapping DSCP v alues, note the fol lo wing information: ?[...]

42-103 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS Note The eighth queue is the strict priori ty queue in the output of th e show queueing interface command. This exampl e sho ws ho w to veri fy the conf iguration: Router# show queueing interface ten[...]

42-104 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS When mapping DSCP v alues to the st rict-priority queue, note the fo llo wing information: • The queue number is alw ays 1. • Y ou can enter up to 8 DSCP valu es to map to the queue. • Y ou can[...]

42-105 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS This example sho ws how to map the CoS values 0 and 1 to threshold 1 in the standard recei ve queue for Gigabit Ethernet port 1/1 : Router# configure terminal Enter configuration commands, one per li[...]

42-106 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS Mapping CoS Values to Strict-Priority Queues T o map CoS values to the receive and transmit strict-prio rity queues, perform t his task: When mapping CoS v alues to th e strict-priority q ueues, note[...]

42-107 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS Mapping CoS Values to Tail-Drop Thres holds on 1q4t/2q2t LAN Ports Note Enter the show queueing interface { ether net | fastether net | gigabitethernet | tengigabitether net } slot/port | include typ[...]

42-108 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS Allocating Bandwidth Between Standard Transmit Queues The router transmits frames from on e standar d queue at a t ime using one of these dequeuing algorithms, which use percentages or weights to all[...]

42-109 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS T o allocate bandwidth between stan dard transmit queues, p erform this task: This exampl e sho ws ho w to allocate a 3-to-1 bandw idth ratio for Gigabi t Ethernet port 1/2: Router# configure termina[...]

42-110 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Configuring PFC QoS Setting the Receive-Queue Size Ratio Y ou can set the size ratio betwee n the standard receiv e queues on 2q8t , 8q4t , and 8q8t port s and between the strict-priority and st andard receiv e queues o[...]

42-111 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Configuring PFC QoS Configuring the Transmit-Queue Size Ratio T o configure the transmit-queue size ratio, perform th is task: When configuring the transmit-qu eue size ratio between transmit queues, note the f ollo win[...]

42-112 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Common QoS Scenarios This exampl e sho ws ho w to set the transmit- queue size ratio for Gigabit Et hernet port 1/2: Router# configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router(config)[...]

42-113 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Common Qo S Scena rios These are the three traff ic classes in the sample network: • Vo i c e • High-priority appli cation traf fic • Best-ef fort traf fic The QoS conf iguration described i n this section iden ti[...]

42-114 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Common QoS Scenarios This is the QoS classif ication scheme f or th e traf fic arri ving on a n access layer port: • V oice traffic: DSCP 46 (highest pr iority) • V oice signaling traff i c: DS CP 24 (medium priorit[...]

42-115 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Common Qo S Scena rios After you create the class maps, create a policy map th at defines the action of the QoS policy so t hat it sets a particular DSCP value for each traff ic type or traff ic class. This example crea[...]

42-116 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Common QoS Scenarios Class Map match-any class-default (id 0) Match any Class Map match-all CLASSIFY-PC-SAP (id 2) Match access-group name CLASSIFY-PC-SAP Class Map match-all CLASSIFY-VOICE-SIGNAL (id 4) Match access-gr[...]

42-117 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Common Qo S Scena rios If you know that all traf fic entering a particular port can be trusted (a s is the case on access-distrib ution or distrib ution-core upli nk ports), you can use the po rt trust conf iguration. U[...]

42-118 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Common QoS Scenarios T o assign traffi c to these queues, you need to configur e a mapping of priority v alues to queues. QoS uses the DSCP-to-CoS map to map the 64 possible outgoing D SCP v alues to the eight possible [...]

42-119 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Common Qo S Scena rios 3 5 3 6 3 7 3 8 4 1 5 <output truncated> Y ou want voi ce traf fi c mapped to the strict prior ity queue, which is queue 4 on 1 p3q8t ports. The exam ple maps the DS CP 46 v oice traf fic to[...]

42-120 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS Common QoS Scenarios The WRR algorithm uses relativ e weights that are assigned to the WRR queues. If there are three queues and their weights are 22:33:45 (which are the defa ult settings), then queue 1 gets only 22 pe[...]

42-121 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS Common Qo S Scena rios The difference between this policer conf iguration and the marking conf iguration is the polic y-map action statements. The marking example uses the set dscp command to mark the traf fic with a pa[...]

42-122 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Glossar y PFC QoS Glossary This section defines some of the QoS te rminology us ed in this chap ter: • Buffer s —A storage area used for handling data in tran sit. Buffers are used in internetworking to comp[...]

42-123 Cisco 7600 Series Router Cisco IOS Softwa re C onfiguration Guide, Release 12.2SX OL-4266-08 Chapter 42 Configuring PFC QoS PFC QoS Glossary • Marking is the process of set ting a Layer 3 DSCP value in a pack et; in this pub lication, the def inition of marking is e xtended to include set ting Layer 2 CoS values. Mar king changes the v alu[...]

42-124 Cisco 7600 Series Router Cisco IOS Software Configura tion Guide, Release 12.2SX OL-4266-08 Chapter 42 Configu ring PFC QoS PFC QoS Glossar y[...]