Example for Configuring Layer 2 Remote Port Mirroring

Networking Requirements

In Figure 1, the administrative department of a company accesses the Internet through SwitchA, and the monitoring device (Server) is connected to SwitchA through SwitchB.

Internet-bound traffic from the administrative department needs to be remotely monitored by the Server.

Figure 1 Layer 2 remote port mirroring networking

Configuration Roadmap

The configuration roadmap is as follows:

Configure GE0/0/2 of SwitchA as a Layer 2 remote observing port to forward mirrored packets to the specified VLAN.
Configure GE0/0/1 of SwitchA as a mirrored port to copy Internet-bound traffic from the administrative department and send the traffic to the Layer 2 remote observing port.
Create a VLAN on SwitchB, disable MAC address learning in this VLAN, and add ports to the VLAN to forward the mirrored packets sent from the observing port to the Server.

Procedure

Configure an observing port on SwitchA.
# Configure GE0/0/2 of SwitchA as a Layer 2 remote observing port and configure VLAN 10 as the Layer 2 remote mirroring VLAN.
```
<HUAWEI> system-view
[HUAWEI] sysname SwitchA
[SwitchA] observe-port 1 interface gigabitethernet 0/0/2 vlan 10
```
# Disable the observing port from forwarding data packets.
```
[SwitchA] observe-port 1 forwarding disable
```
Configure a mirrored port on SwitchA.
# Configure GE0/0/1 of SwitchA as a mirrored port to copy the packets received by the mirrored port and send them to the Layer 2 remote observing port.
```
[SwitchA] interface gigabitethernet 0/0/1
[SwitchA-GigabitEthernet0/0/1] port-mirroring to observe-port 1 inbound
[SwitchA-GigabitEthernet0/0/1] return
```

Create a VLAN on SwitchB and add ports to the VLAN.

# Create VLAN 10 on SwitchB, disable MAC address learning in VLAN 10, and add GE0/0/1 and GE0/0/2 to VLAN 10.

VLAN 10 is used for forwarding only mirrored packets. If VLAN 10 already exists and has learned MAC address entries, run the undo mac-address vlan vlan-id command in the system view to delete all MAC address entries in VLAN 10.

<HUAWEI> system-view
[HUAWEI] sysname SwitchB
[SwitchB] vlan 10
[SwitchB-vlan10] mac-address learning disable
[SwitchB-vlan10] quit
[SwitchB] interface gigabitethernet 0/0/1
[SwitchB-GigabitEthernet0/0/1] port link-type access
[SwitchB-GigabitEthernet0/0/1] port default vlan 10
[SwitchB-GigabitEthernet0/0/1] quit
[SwitchB] interface gigabitethernet 0/0/2
[SwitchB-GigabitEthernet0/0/2] port link-type trunk
[SwitchB-GigabitEthernet0/0/2] port trunk allow-pass vlan 10
[SwitchB-GigabitEthernet0/0/2] return

Verify the configuration.

# Check the observing port configuration.

<SwitchA> display observe-port
  ----------------------------------------------------------------------
  Index          : 1
  Untag-packet   : No
  Forwarding     : No
  Interface      : GigabitEthernet0/0/2
  Vlan           : 10
  ----------------------------------------------------------------------

# Check the mirrored port configuration.

<SwitchA> display port-mirroring
  ----------------------------------------------------------------------
  Observe-port 1 : GigabitEthernet0/0/2
  ----------------------------------------------------------------------
  Port-mirror:
  ----------------------------------------------------------------------
       Mirror-port               Direction  Observe-port
  ----------------------------------------------------------------------
  1    GigabitEthernet0/0/1      Inbound    Observe-port 1
  ----------------------------------------------------------------------