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Catalyst2950 and Catalyst2955 Switch Software Configuration Guide
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Chapter25 Configuring SPAN and RSPAN
Configuring SPAN
•When SPAN is enabled, configuration changes have these results:
–
If you change the VLAN configuration of a destination port, the change is not effective until
SPAN is disabled.
–
If you disable all source ports or the destination port, the SPAN function stops until both a
source and the destination port are enabled.
Creating a SPAN Session and Specifying Ports to Monitor
Beginning in privileged EXEC mode, follow these steps to create a SPAN session and specify the source
(monitored) and destination (monitoring) ports:
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 no monitor session {session_number | all |
local | remote}Clear any existing SPAN configuration for the session.
For session_number, specify 1.
Specify all to remove all SPAN sessions, local to remove all local
sessions, or remote to remove all remote SPAN sessions.
Step3 monitor session session_number source
interface interface-id [, | -] [both | rx | tx]Specify the SPAN session and the source port (monitored port).
For session_number, specify 1.
For interface-id, specify the source port to monitor. Valid interfaces
include physical interfaces and port-channel logical interfaces
(port-channel port-channel-number).
(Optional) [, | -] Specify a series or range of interfaces. Enter a space
before and after the comma; enter a space before and after the
hyphen.
(Optional) Specify the direction of traffic to monitor. If you do not
specify a traffic direction, the source interface sends both sent and
received traffic.
•both—Monitor both received and sent traffic.
•rx—Monitor received traffic.
•tx—Monitor sent traffic.
Step4 monitor session session_number
destination interface interface-id
[encapsulation {dot1q}]
Specify the SPAN session and the destination port (monitoring port).
For session_number, specify 1.
For interface-id, specify the destination port. Valid interf aces include
physical interfaces.
(Optional) Specify the encapsulation header for outgoing packets. If
not specified, packets are sent in native form.
•dot1q—Use 802.1Q encapsulation.
Step5 end Return to privileged EXEC mode.
Step6 show monitor [session session_number] Verify your entries.
Step7 copy running-config startup-config (Optional) Save your entries in the configuration file.