Example: Configuring and Verifying Two-Rate Tricolor Marking

This example configures a two-rate tricolor marking policer on an input Gigabit Ethernet interface and shows commands to verify its operation.

Traffic enters the Gigabit Ethernet interface and exits a SONET/SDH OC12 interface. Oversubscription occurs when you send line-rate traffic from the Gigabit Ethernet interface out the OC12 interface.

Figure 10 shows the sample topology.

Figure 10: Tricolor Marking Sample Topology

Image g016708.gif

Applying a Policer to the Input Interface

The tricolor marking and policer are applied on the ingress Gigabit Ethernet interface. Incoming packets are metered. Packets that do not exceed the CIR are marked with low loss priority. Packets that exceed the CIR but do not exceed the PIR are marked with medium-high loss priority. Packets that exceed the PIR are marked with high loss priority.

[edit]interfaces {ge-1/2/1 {unit 0 {family inet {filter {input trtcm-filter;}}}}}firewall {three-color-policer trtcm1 {two-rate {color-aware;committed-information-rate 100m;committed-burst-size 65536;peak-information-rate 200m;peak-burst-size 131072;}}filter trtcm-filter {term one {then {three-color-policer {two-rate trtcm1;}}}}}

Applying Profiles to the Output Interface

Transmission scheduling and weighted random early detection (WRED) profiles are applied on the output OC12 interface. The software drops traffic in the low, medium-high, and high drop priorities proportionally to the configured drop profiles.

[edit]class-of-service {drop-profiles {low-tcm {fill-level 80 drop-probability 100;}med-tcm {fill-level 40 drop-probability 100;}high-tcm {fill-level 10 drop-probability 100;}}tri-color;interfaces {so-1/1/0 {scheduler-map tcm-sched;}}scheduler-maps {tcm-sched {forwarding-class queue-0 scheduler q0-sched;forwarding-class queue-3 scheduler q3-sched;}}schedulers {q0-sched {transmit-rate percent 50;buffer-size percent 50;drop-profile-map loss-priority low protocol any drop-profile low-tcm;drop-profile-map loss-priority medium-high protocol any drop-profile med-tcm;drop-profile-map loss-priority high protocol any drop-profile high-tcm;}q3-sched {transmit-rate percent 50;buffer-size percent 50;}}}

Marking Packets with Medium-Low Loss Priority

In another example, the 4PLP filter and policer causes certain packets to be marked with medium-low loss priority.

interfaces {ge-7/2/0 {unit 0 {family inet {filter {input 4PLP;}policer {input 4PLP;}address 10.45.10.2/30;}}}} firewall {three-color-policer trTCM {two-rate {color-blind;committed-information-rate 400m;committed-burst-size 100m;peak-information-rate 1g;peak-burst-size 500m;}}policer 4PLP {if-exceeding {bandwidth-limit 40k;burst-size-limit 4k;}then loss-priority medium-low;}family inet {filter 4PLP {term 0 {from {precedence 1;}then loss-priority medium-low;}}filter filter_trTCM {term default {then {three-color-policer {two-rate trTCM;}}}}}}

Verifying Two-Rate Tricolor Marking Operation

The following operational mode commands are useful for checking the results of your configuration:

show class-of-service forwarding-table classifiers
show interfaces interface-name extensive
show interfaces queue interface-name

For information about these commands, see the Junos Interfaces Command Reference and Junos System Basics and Services Command Reference.