Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?

 

Defining CoS Rewrite Rules (CLI Procedure)

 

You configure rewrite rules to alter CoS values in outgoing packets on the outbound interfaces of an EX Series switch to match the policies of a targeted peer. Policy matching allows the downstream routing platform or switch in a neighboring network to classify each packet into the appropriate service group.

To configure a CoS rewrite rule, create the rule by giving it a name and associating it with a forwarding class, loss priority, and a code point, thus creating a rewrite table, and you can enable the rewrite rule on an interface. On EX Series switches except EX4300 switches, you can also enable a rewrite rule on routed VLAN interfaces (RVIs). On EX4300 switches, you can also enable rewrite rules on integrated routing and bridging (IRB) interfaces. If you need to customize a rewrite rule, you can create a customized rewrite rule using a firewall filter configuration. You can configure CoS rewrite rules for DSCP, IP precedence and IEEE 802.1p.

You can configure rewrite rules for the following CoS marker types:

  • dscp and dscp-ipv6—Handles incoming IPv4 and IPv6 packets, respectively. On EX4300 switches, you cannot configure DSCP IPv4 and DSCP IPv6 rewrite rules on the same interface. If you configure a DSCP IPv4 rewrite rule on an interface to rewrite IPv4 traffic, then the same rewrite rule is applied to IPv6 traffic also on that interface, and vice versa.

  • ieee-802.1—Handles Layer 2 CoS.

  • inet-precedence—Handles incoming IPv4 packets. IP precedence mapping requires only the higher order three bits of the DSCP field.

Note

To replace an existing rewrite rule on the interface with a new rewrite rule of the same type, first explicitly remove the rewrite rule and then apply the new rule.

To create IEEE 802.1p rewrite rules and enable them on Layer 2 interfaces:

  • To create an IEEE 802.1p rewrite rule named customup-rw in the rewrite table for all Layer 2 interfaces:

    [edit class-of-service rewrite-rules]

    user@switch# set ieee-802.1 customup-rw forwarding-class be loss-priority low code-point 000

    user@switch# set ieee-802.1 customup-rw forwarding-class be loss-priority high code-point 001

    user@switch# set ieee-802.1 customup-rw forwarding-class af loss-priority low code-point 010

    user@switch# set ieee-802.1 customup-rw forwarding-class af loss-priority high code-point 011

    user@switch# set ieee-802.1 customup-rw forwarding-class ef loss-priority low code-point 100

    user@switch# set ieee-802.1 customup-rw forwarding-class ef loss-priority high code-point 101

    user@switch# set ieee-802.1 customup-rw forwarding-class nc loss-priority low code-point 110

    user@switch# set ieee-802.1 customup-rw forwarding-class nc loss-priority high code-point 111
  • To enable an IEEE 802.1p rewrite rule named customup-rw on a Layer 2 interface:

    [edit]

    user@switch# set class-of-service interfaces ge-0/0/0 unit 0 rewrite-rules ieee-802.1 customup-rw

    (On EX4300 switches) To enable an IEEE 802.1p rewrite rule named customup-rw on a Layer 2 interface:

    [edit]

    user@switch# set class-of-service interfaces ge-0/0/0 rewrite-rules ieee-802.1 customup-rw
  • To enable an IEEE 802.1p rewrite rule named customup-rw on all Gigabit Ethernet interfaces on the switch, use wildcards for the interface name and logical-interface (unit) number:

    [edit]

    user@switch# set class-of-service interfaces ge-* unit * rewrite-rules customup-rw

    (On EX4300 switches) To enable an IEEE 802.1p rewrite rule named customup-rw on all Gigabit Ethernet interfaces on the switch, use wildcards for the interface name:

    [edit]

    user@switch# set class-of-service interfaces ge-* rewrite-rules customup-rw