Configuring RSPAN Mirroring

RSPAN, also known as Remote Switched Port Analyzer (SPAN), enables monitoring of traffic from multiple sources distributed over multiple switches. RSPAN enables consolidation of network monitoring at a single location. It works by mirroring target traffic from multiple source ports into a particular VLAN dedicated for monitoring purposes.

About this task

Do the following to configure RSPAN Mirroring where the source port is a Physical Ethernet port and the destination ports are a RSPAN VLAN and another Physical Ethernet port.

Procedure

Access global configuration mode.
```
SLX# configure terminal
```
(If necessary) Disable protocols on the destination interface.
This example disables LLDP.
1. Enter interface configuration mode.
```
SLX (config)# interface ethernet 0/2
```
2. Disable LLDP.
```
SLX (conf-if-eth-0/2)# lldp disable
                            
```
3. Exit interface configuration mode.
```
SLX (conf-if-eth-0/2)# exit
```

Create the port mirroring session and assign a number.

SLX (config)# monitor session 28
SLX (config-session-28)#

Identify the source Ethernet interface port, the destination RSPAN VLAN, the interface and port (for the ethernet port through which the RSPAN VLAN is reachable), and the direction of the traffic to monitor. Then create the appropriate mirroring configuration.
```
SLX (config-session-28)# source ethernet 0/1 destination rspan-vlan 120 ethernet 0/3         direction rx
SLX (config-session-28)#
                    
```

Results

The ingress traffic on ethernet port 0/1 is now mirrored to the destination RSPAN VLAN through the configured ethernet port.

Example

This example summarizes the above configuration

SLX# configure terminal
SLX (config)# interface ethernet 0/3
SLX (conf-if-eth-0/3)# lldp disable
SLX (conf-if-eth-0/3)# exit
SLX (config)# monitor session 28
SLX (config-session-28)# source ethernet 0/1 destination rspan-vlan 120 ethernet 0/3 direction rx

This example shows the configuration of RSPAN mirroring from a source ethernet port to a destination RSPAN VLAN on a port channel.

SLX (config)# monitor session 30
SLX (config-session-30)# source ethernet 0/1 destination rspan-vlan 120 port-channel 2 direction tx