Apply Behavior Aggregate Classifiers to Interfaces

When you apply BA classifiers to an interface, you can use interface wildcards for the interface-name and logical-unit-number.

Family-specific classifiers take precedence over IEEE 802.1p BA classifiers. For example, if you configure a logical interface to use both an MPLS EXP and an IEEE 802.1p classifier, the EXP classifier takes precedence. MPLS-labeled packets are evaluated by the EXP classifier, and all other packets are evaluated by the IEEE 802.1p classifier. The same is true about other classifiers when combined with IEEE 802.1p classifiers on the same logical interface.

You can configure user-defined DSCP-based BA classification for MPLS interfaces or VPLS or L3 VPN routing instances (LSI interfaces). Junos does not support DSCP-based classification for MPLS packets for L2 VPNs.

Note:

If you do not apply a DSCP classifier, Junos applies the default EXP classifier to MPLS traffic. You might need to maintain the original classifier of the incoming packet, where you neither want to configure a custom classifier for the interface nor accept the default classifier, which would override the original classifier. In that case, you can apply the no-default option for the interface. For example:

You can apply DSCP classification for MPLS traffic in the following usage scenarios:

• In an L3 VPN using a label-switched interface (LSI) routing instance:

  • DSCP classifier applied under [edit class-of-service routing-instances] on the egress PE router.

• In VPLS using an LSI routing instance

  • DSCP classifier applied under [edit class-of-service routing-instances] on the egress PE router.

• In an L3 VPN using a virtual tunnel (VT) routing instance

  • DSCP classifier applied under [edit class-of-service interfaces] on the core-facing interface on the egress PE router.

• In VPLS using the VT routing instance

• MPLS forwarding

  • DSCP classifier applied under [edit class-of-service interfaces] on the ingress core-facing interface on the provider (P) or egress PE router.

MPLS forwarding when the label stacking is greater than 2 is not supported.

You can apply BA classifiers to a routing instance or a logical interface, depending on where you want to classify the packets:

• To classify MPLS packets on the routing instance at the egress PE, include the dscp or dscp-ipv6 statements at the [edit class-of-service routing-instances routing-instance-name classifiers] hierarchy level. For details, see Applying MPLS EXP Classifiers to Routing Instances.

• To classify MPLS packets at the core-facing interface, apply the classifier at the [edit class-of-service interface interface-name unit unit-name classifiers (dscp | dscp-ipv6) classifier-name family mpls] hierarchy level. The following procedure describes this method.

In the following example, you define a DSCP classifier for IPv4 named dscp-ipv4-classifier and a corresponding IPv6 DSCP classifier for the fc-af11-class forwarding class. You then apply the IPv4 classifier to MPLS traffic and the IPv6 classifier to Internet traffic on interface ge-2/0/3.0. Or you can apply the same classifier to both MPLS and IP traffic on interface ge-2/2/0. This example shows both of these methods.