Applying Rewrite Rules to Output Logical Interfaces
To assign the rewrite-rules configuration to the output logical interface, include the
rewrite-rules statement at the [edit class-of-service
interfaces interface-name unit
logical-unit-number] hierarchy level:
[edit class-of-service interfaces interface-name unit logical-unit-number] rewrite-rules { dscp (rewrite-name | <default>) protocol protocol-types; dscp-ipv6 (rewrite-name | <default>) protocol protocol-types; exp (rewrite-name | <default>) protocol protocol-types; exp-push-push-push <default>; exp-swap-push-push <default>; ieee-802.1 (rewrite-name | <default>) inet-prec vlan-tag (outer | outer-and-inner); inet-precedence (rewrite-name | <default>) protocol protocol-types; inet6-precedence (rewrite-name | <default>) protocol protocol-types; }
You can combine the dscp or inet-prec and
exp options to set the DSCP or IP precedence bits and MPLS EXP bits
independently on IP packets entering an MPLS tunnel.
Logical interfaces do not support multiple dscp rewrite rules or
multiple dscp-ipv6 rewrite rules for the same protocol.
In the following example, the DSCP bits specified in ss-dscp are applied
to packets entering the MPLS tunnel on ge-2/1/1, and the DSCP bits
specified in ss-v6dscp are applied to IPv6 packets. The EXP bits are
set to the bit configuration specified in ss-exp:
[edit class-of-service interfaces]
ge-2/1/1
unit 10 {
rewrite-rules {
dscp ss-dscp protocol mpls; # Applies to IPv4 packets entering MPLS tunnel
dscp-ipv6 ss-v6dscp protocol mpls; # Applies to IPv6 packets entering MPLS tunnel
exp ss-exp; # Sets label EXP bits independently
}
}
}
You can use interface wildcards for interface-name
and logical-unit-number. You can also include
Layer 2 and Layer 3 rewrite information in the same configuration.
Platform-Specific Behavior
Use the following table to review platform-specific behaviors for your platforms.
|
Platform |
Difference |
|---|---|
|
ACX5448 |
ACX5448 supports rewrite on services such as:
For L2, rewrite information resides in the VLAN translation entry at the egress side. Without that entry, rewrite does not take place. For VLAN-CCC (local cross-connect), the rewrite is supported by enabling VLAN translation entry in the same manner as that for L2. |