troubleshooting Question

RSPAN Using Cisco Catalyst 3560G as Source and 3750G as Destination Switches

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carnescFlag for United States of America asked on
Networking Hardware-OtherNetwork Management
6 Comments1 Solution3912 ViewsLast Modified:
Goal: Mirror all voice traffic for recording.

Voice VLAN to monitor: 100 (on the 3560)
RSPAN VLAN to create: 500 (on all involved switches)
Dedicated destination port and switch: Gi1/0/3 (on the 3750)
See attached, current configuration

As a test, Wireshark is running on a laptop connnected to the destination port. The destination port is itself configured for VLAN 100, the same VLAN as that being monitored. According to documentation, destination ports configured within a monitored VLAN are merely excluded from monitoring, so I assume this setup is acceptable.

Not that it can generally get anywhere as a designated RSPAN destination, but the capture laptop is configured with a valid IP on the 100 VLAN.

Both switches are interconnected with all VLANs allowed on uplink trunks, but I am not receiving packets with Wireshark beyond broadcasts by the local machine.

Specific Config Questions:
1. Are my monitoring sessions properly configured?
2. Is my destination port and capture device properly configured?
3. Any suggestions?

Other questions:
1. Is port security a problem for egress monitoring on source switches or just the destination port? In other words, am I going to have to remove port security from all voice switchports in order to get this to work?
3. Any gotcha advice with respect to bandwidth, RAM, CPU utilization?

I've read Cisco's documentation on RSPAN, but cannot seem to get clear on answers to the above questions. Thanks for any help!
************************************************
Example 3750 destination switch and port
************************************************
 
3750(config)#vlan 500
3750(config-vlan)#remote-span
3750(config-vlan)#end
 
3750(config)#monitor session 1 source remote vlan 100
3750(config)#monitor session 1 destination interface Gi1/0/3 both
 
3750(config)#int Gi1/0/3
3750(config-if)#switchport access vlan 100
3750(config-if)#do wri mem
 
************************************************
Example 3560 source switch to monitor
************************************************
 
3560(config)#vlan 500
3560(config-vlan)#remote-span
3560(config-vlan)#end
 
3560(config)#monitor session 1 source vlan 100
3560(config)#monitor session 1 destination remote vlan 500
3560(config)#end
3560(config)#do wri mem
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