Cisco 2950G 24 - Catalyst Switch - Specifying Vlans to Monitor

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Catalyst 2950 Desktop Switch Software Configuration Guide
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Chapter 21 Configuring SPAN and RSPAN
Configuring RSPAN
Specifying VLANs to Monitor
VLAN monitoring is similar to port monitoring. Beginning in privileged EXEC mode, follow these steps
to specify VLANs to monitor:
To remove one or more source VLANs from the RSPAN session, use the no monitor session
session_number source vlan vlan-id rx global configuration command.
This example shows how to clear any existing configuration on RSPAN session 2, configure RSPAN
session 2 to monitor received traffic on all ports belonging to VLANs 1 through 3, and send it to
destination remote VLAN 902 using reflector port 7. The configuration is then modified to also monitor
received traffic on all ports belonging to VLAN 10.
Switch(config)# no monitor session 2
Switch(config)# monitor session 2 source vlan 1 - 3 rx
Switch(config)# monitor session 2 destination remote vlan 902 reflector-port
gigabitethernet0/7
Switch(config)# monitor session 2 source vlan 10 rx
Switch(config)# end
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
no monitor session {session_number | all
| local | remote}
Clear any existing SPAN configuration for the session.
For session_number, specify 1 or 2.
Specify all to remove all SPAN sessions, local to remove all local
sessions, or remote to remove all remote SPAN sessions.
Step 3
monitor session session_number source
vlan vlan-id [, | -] rx
Specify the RSPAN session and the source VLANs (monitored
VLANs). You can monitor only received (rx) traffic on VLANs.
For session_number, specify 1 or 2.
For vlan-id, the range is 1 to 4094; do not enter leading zeros.
(Optional) Use a comma (,) to specify a series of VLANs, or use a
hyphen (-) to specify a range of VLANs. Enter a space after the comma;
enter a space before and after the hyphen.
Step 4
monitor session session_number
destination remote vlan vlan-id reflector
port interface
Specify the RSPAN session, the destination remote VLAN, and the
reflector port.
For session_number, enter 1 or 2.
For vlan-id, specify the RSPAN VLAN to carry the monitored traffic to
the destination port.
For interface, specify the interface that will flood the RSPAN traffic to
the RSPAN VLAN.
Step 5
end Return to privileged EXEC mode.
Step 6
show monitor [session session_number] Verify your entries.
Step 7
copy running-config startup-config (Optional) Save your entries in the configuration file.