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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 monitor ing is similar to port monitoring. Be ginning in pri vileged EXEC mode, follo w these steps
to specify VLANs to monitor:
To remove one or m ore source VL A Ns fr om the RSPAN se ssion, us e the no monitor session
session_number source vlan vlan-id rx global co nfigurati on comm a nd.
This exam ple sh ows how to cle ar a ny existing configura tion on R S PAN session 2, configure RSPAN
session 2 to moni tor received traffic on all ports belongi ng to VLAN s 1 throug h 3, and send it to
destination remote VLAN 902 using reflector port 7. The conf iguration is then modif ied to also monitor
received traffic on al l po rts be longi ng to VLA N 1 0.
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 globa l configurati on mode.
Step 2 no monitor sessio n { session_number | all
| local | remote}Clear any existing SPAN configuration for the session.
For session_number, speci fy 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 s ession session_number source
vlan vlan-id [, | -] rx Speci fy the RSPAN session an d the sourc e VLANs (mon itore d
VLANs ). You can mo nitor onl y received (rx) traffic on VLANs.
For session_number, speci fy 1 or 2.
For vlan-id, the range is 1 to 4094; do not enter leading zeros.
(Opti onal) Us e a comm a (,) to specify a series of VLANs, or use a
hyphen (-) to specify a range of VLANs. Enter a space after the comma;
enter a spac e before a nd after the hyphen.
Step 4 monitor s ession session_number
desti nat io n r e mot e v la n vlan-id reflector
port interface
Specify the RSPAN session, the destination remote VLAN, and the
reflec tor po rt.
For session_number, enter 1 or 2.
For vlan-id, specify the RSPAN VLA N to carry th e monitored tr af fic to
the de st inat ion por t.
For interface, specify the interface that will flood the RSPAN traff ic 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 (Optiona l) Save your entries in the co nfigurati on file.