Configuring QoS

SR OS implements Quality of Service (QoS) with a four-step process:
  1. Classification
  2. Queuing
  3. Scheduling
  4. Re-marking

For more information about QoS configuration, see the 7450 ESS, 7750 SR, 7950 XRS, and VSR Quality of Service Guide.

Classification

This following example displays packet classification using DSCP, EXP, protocol and destination IP address. The classification policy is then applied to the interface. For QoS on VPRN interfaces, similar configurations can be applied on the sap-ingress and sap-egress contexts within configure qos.

Configuring QoS classification

configure qos match-list ip-prefix-list “Peering-Core” prefix 10.10.10.0/24
configure qos network "Peering-Ingress-QoS" policy-id 10
configure qos network "Peering-Ingress-QoS" ingress dscp be fc be
configure qos network "Peering-Ingress-QoS" ingress dscp be profile out
configure qos network "Peering-Ingress-QoS" ingress lsp-exp 6 fc h1
configure qos network "Peering-Ingress-QoS" ingress lsp-exp 6 profile in
configure qos network "Peering-Ingress-QoS" ingress ip-criteria entry 10 match protocol tcp
configure qos network "Peering-Ingress-QoS" ingress ip-criteria entry 10 match dst-ip ip-prefix-list "Peering-Core"
configure qos network "Peering-Ingress-QoS" ingress ip-criteria entry 10 action fc ef

configure router "Base" interface "To-Peering-LAN" qos network-policy "Peering-Ingress-QoS"

Queuing

The following example displays a sample configuration for the queuing step in the QoS packet flow. The queuing policy is applied to the FP context of the card.

Configuring QoS queuing

configure qos network-queue "Peering-Queue" fc be queue 1
configure qos network-queue "Peering-Queue" fc ef queue 6
configure qos network-queue "Peering-Queue" fc h1 queue 7
configure qos network-queue "Peering-Queue" fc nc queue 8
configure qos network-queue "Peering-Queue" queue 1 mbs 50.0
configure qos network-queue "Peering-Queue" queue 1 rate pir 90
configure qos network-queue "Peering-Queue" queue 1 rate cir 10
configure qos network-queue "Peering-Queue" queue 6 cbs 70.0
configure qos network-queue "Peering-Queue" queue 6 mbs 100.0
configure qos network-queue "Peering-Queue" queue 6 rate pir 100
configure qos network-queue "Peering-Queue" queue 6 rate cir 100
configure qos network-queue "Peering-Queue" queue 7 rate pir 100
configure qos network-queue "Peering-Queue" queue 7 rate cir 100
configure qos network-queue "Peering-Queue" queue 8 rate pir 10
configure qos network-queue "Peering-Queue" queue 8 rate cir 10

configure card 1 fp 1 ingress network queue-policy "Peering-Queue"

Scheduling

The following example displays a simple port-based scheduler that typically meets the requirements for a peering network. SR OS also supports hierarchical schedulers and slope policies.

After the scheduler policy is defined, it is applied to the physical port context.

Configuring QoS scheduling

configure qos port-scheduler-policy "Peer-Scheduler" max-rate 100000000
configure qos port-scheduler-policy "Peer-Scheduler" level 1 rate pir 90
configure qos port-scheduler-policy "Peer-Scheduler" level 1 rate cir 10
configure qos port-scheduler-policy "Peer-Scheduler" level 6 rate pir max
configure qos port-scheduler-policy "Peer-Scheduler" level 6 rate cir max
configure qos port-scheduler-policy "Peer-Scheduler" level 7 rate pir max
configure qos port-scheduler-policy "Peer-Scheduler" level 7 rate cir max
configure qos port-scheduler-policy "Peer-Scheduler" level 8 rate pir max
configure qos port-scheduler-policy "Peer-Scheduler" level 8 rate cir max

configure port 1/1/c1/1 ethernet egress port-scheduler-policy policy-name "Peer-Scheduler"

Re-marking

Re-marking configuration is done inside the same policy as the classification and is applied under the interface level as shown in the following example.

Configuring QoS re-marking

configure qos network "Peering-Ingress-QoS" egress fc be lsp-exp-in-profile 0
configure qos network "Peering-Ingress-QoS" egress fc be lsp-exp-out-profile 0
configure qos network "Peering-Ingress-QoS" egress fc ef dscp-in-profile af41
configure qos network "Peering-Ingress-QoS" egress fc h1 lsp-exp-in-profile 6

configure router "Base" interface "To-Peering-LAN" qos network-policy "Peering-Ingress-QoS"