(Optional) Configuring the CAR Function for Mirrored Traffic

This section describes how to configure the committed access rate (CAR) function for mirrored traffic to prevent a large amount of mirrored traffic from affecting packet processing.

Context

Before you configure the CAR function for mirrored traffic, configure a mirrored port and an observing port.

**Table 1** Interfaces supporting local mirroring
Interface Type	Mirrored Port	Observing Port
Layer 3 Ethernet main interfaces (including Eth-Trunk interfaces and a Layer 3 main interface configured as a BAS main interface)	Supported	Supported
BAS interface	Supported NOTE: When a VE interface functions as a BAS interface, local flow mirroring is supported only on the access VE interface in hardware loopback mode.	Not supported
Ethernet sub-interfaces (including Eth-Trunk interfaces)	Supported NOTE: After a sub-interface is configured as a dot1q, dot1q VLAN tag termination, QinQ VLAN tag termination, EVC, or BAS sub-interface, the sub-interface still supports mirroring.	Supported NOTE: After a sub-interface is configured as a dot1q VLAN tag termination, QinQ VLAN tag termination, or BAS sub-interface, the sub-interface does not support be configured as an observing port. The observing port can only be configured on the EVC sub-interface with untag or dot1q traffic encapsulation type.

Procedure

Run system-view
The system view is displayed.
When the mirrored port is not an EVC Layer 2 sub-interface,run interface interface-type interface-number
The interface view is displayed.
When an EVC Layer 2 sub-interface or a bridge domain functions as the mirrored port, enter the following views to configure CAR for mirrored traffic:
- If the mirrored port is created in common mode, run interface interface-type interface-number.subnum mode l2
  
  The EVC layer 2 sub-interface view is displayed.
- If the mirrored port is created in mirroring instance mode, run mirror instance instance-name location
  
  A mirroring instance is created, and the mirroring instance view is displayed.
Run port-mirroring car cir cir-value [ pir pir-value ] [ cbs cbs-value [ pbs pbs-value ] ]
The CAR function is configured for mirrored traffic to limit the rate of mirrored packets.