Only single-direction messages can be captured after S12508 is configured with local mirror in both directions

2020-10-16 Published

Network Topology


Problem Description

User feedback can only catch the single side of the message after the 12508 configuration of the local mirror both, so it suspects the equipment failure

Process analysis

Check the configuration and find the port mirroring configuration is configured properly:

mirroring-group 2 local

interface GigabitEthernet1/6/0/32 

 port link-mode bridge 

mirroring-group 2 monitor-port 


# interface Ten-GigabitEthernet1/4/0/18 

 port link-mode bridge

 port link-type trunk 

 undo port trunk permit vlan 1 

 port trunk permit vlan 114 4019 

 qos apply policy SW-02 inbound 

 mirroring-group 2 mirroring-port both 


But it turns out that in addition to the local mirroring configuration, the device is configured with a flow mirroring as follows:

traffic classifier SW-02 operator 

and if-match acl 3334

traffic behavior SW-02 

 mirror-to vlan 500 

qos policy SW-02 

 classifier SW-02 behavior SW-02

The engineer consulted the manual and found the following limitations on the device. When the local mirroring and flow mirroring are configured at the same time, only the flow mirroring will take effect.


Remove the flow mirroring configuration to make the local mirroring take effect.