Example: Configuring Filtering of Frames by Packet Loss Priority

To configure an MX Series router firewall filter to provide matching on the packet loss priority (PLP) level carried in the frame, use the loss-priority or loss-priority-except match condition. Packet loss priority matching is available for all protocols. For more detailed information about configuring firewall filters and configuring filter match conditions for Layer 2 bridging traffic on the MX Series routers, see the Junos OS Routing Policy Configuration Guide .

Note: Layer 2 bridging is supported only on the MX Series routers. For more information about how to configure Layer 2 bridging, see the Junos OS Network Interfaces Configuration Guide, the Junos OS Routing Protocols Configuration Guide , and the Junos OS Feature Guides.

This example Layer 2 bridging firewall filter finds any incoming frames with a packet loss priority (PLP) level of medium-high, and then classifies the packet in the expedited-forwarding default forwarding class.

Note: This example does not present exhaustive configuration listings for all routers in the figures. However, you can use this example with a broader configuration strategy to complete the MX Series router network Ethernet Operations, Administration, and Maintenance (OAM) configurations.

1. Configure the firewall filter filter-plp-configure-forwarding:

   [edit firewall]family bridge {filter filter-plp-configure-forwarding {term 0 {from {loss-priority medium-high;}then forwarding-class expedited-forwarding;}}}

2. Configure a Layer 2 bridging domain bd for the ge-0/0/0 interface (that has already been configured at the [edit interfaces] hierarchy level):

   [edit bridge-domains]bd {domain-type bridge {interface ge-0/0/0;}}

3. Apply the filter filter-plp-configure-forwarding as an input filter to the ge-0/0/0 interface:

   [edit interfaces]ge-0/0/0 {unit 0 {family bridge {filter {input filter-plp-configure-forwarding; }}}}