QoS

SR OS implements Quality of Service (QoS) with a four-step process: classification, queueing, scheduling, and (re)marking.

QoS policies can be applied under the following contexts:

SAP ingress (for traffic ingressing a service)
SAP egress (for traffic egressing a service)
network ingress (for traffic ingressing a network-facing port or uplink)
network egress (for traffic egressing a network-facing port or uplink)

See the 7450 ESS, 7750 SR, 7950 XRS, and VSR Quality of Service Guide for detailed information about QoS configuration.

Classification

At service ingress, classification is configured in a sap-ingress policy.

/configure qos sap-ingress "CE-ingress-QoS" dscp cs1 fc "af"

The sap-ingress policy is applied to the service SAP.

/configure service epipe "Epipe-VLAN100" sap 1/1/c10/1:100 ingress qos sap-ingress policy-name "CE-ingress-QoS"

At network ingress, classification is configured in a network policy.

/configure qos network "Network-QoS" policy-id 10
/configure qos network "Network-QoS" ingress dscp cs1 fc af
/configure qos network "Network-QoS" ingress dscp cs1 profile in
/configure qos network "Network-QoS" ingress lsp-exp 6 fc h1
/configure qos network "Network-QoS" ingress lsp-exp 6 profile in

The network classification policy is applied to the network-facing interface.

/configure router "Base" interface "To-P1" qos network-policy "Network-QoS"

See the relevant section for each service type for examples of applying QoS classification to that specific service type.

Queuing

At service ingress, queuing is configured in a sap-ingress policy.

/configure qos sap-ingress "CE-ingress-QoS" policy-id 11
/configure qos sap-ingress "CE-ingress-QoS" queue 2 rate pir 100
/configure qos sap-ingress "CE-ingress-QoS" queue 2 rate cir 100
/configure qos sap-ingress "CE-ingress-QoS" fc "af" queue 2
/configure qos sap-ingress "CE-ingress-QoS" fc "af" profile in

At service egress, queuing is configured in a sap-egress policy.

/configure qos sap-egress "CE-egress-QoS" policy-id 12
/configure qos sap-egress "CE-egress-QoS" queue 3 rate pir 100
/configure qos sap-egress "CE-egress-QoS" queue 3 rate cir 100
/configure qos sap-egress "CE-egress-QoS" fc be queue 3

Both sap-ingress and sap-egress policies are applied under the service SAP.

/configure service epipe "Epipe-VLAN100" sap 1/1/c10/1:100 ingress qos sap-ingress policy-name "CE-ingress-QoS"
/configure service epipe "Epipe-VLAN100" sap 1/1/c10/1:100 egress qos sap-egress policy-name "CE-egress-QoS"

At network ingress and egress, queuing is configured in a network-queue policy.

/configure qos network-queue "Network-queue" fc af queue 3
/configure qos network-queue "Network-queue" fc ef queue 2
/configure qos network-queue "Network-queue" queue 2 rate pir 15
/configure qos network-queue "Network-queue" queue 2 rate cir 10
/configure qos network-queue "Network-queue" queue 3 rate pir 10
/configure qos network-queue "Network-queue" queue 3 rate cir 5

For ingress network queueing, the queuing policy is applied under the FP context of the line card.

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

For egress network queuing, the queuing policy is applied under the physical port.

/configure port 1/1/c1/1 ethernet network egress queue-policy "Network-queue"

Scheduling

This example shows a simple port-based scheduler that can be applied to schedule traffic out of a network-facing port. SR OS also supports hierarchical schedulers and slope policies.

Similar policies can also be applied under a sap-egress policy to schedule multiple traffic types at service egress.

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

The port-based scheduler policy is applied to the physical port.

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

Remarking

At service egress, remarking is configured in the sap-egress policy.

/configure qos sap-egress "CE-egress-QoS" fc be dscp in-profile cp31
/configure qos sap-egress "CE-egress-QoS" fc be dscp out-profile cp31
/configure qos sap-egress "CE-egress-QoS" fc af dscp in-profile cs4
/configure qos sap-egress "CE-egress-QoS" fc af dscp out-profile cs4

The sap-egress policy is applied under the service SAP context.

/configure service epipe "Epipe-VLAN100" sap 1/1/c10/1:100 egress qos sap-egress policy-name "CE-egress-QoS"

At network egress, remarking is configured in the network policy.

/configure qos network "Network-QoS" egress fc be lsp-exp-in-profile 0
/configure qos network "Network-QoS" egress fc be lsp-exp-out-profile 0
/configure qos network "Network-QoS" egress fc af dscp-in-profile cs1
/configure qos network "Network-QoS" egress fc h1 lsp-exp-in-profile 6

The remarking policy is applied under the interface.

/configure router "Base" interface "To-P1" qos network-policy "Network-QoS"

See QoS for information about relevant QoS show commands.