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New Member

About Mirroring for Giga port

Hi all !

I try to do mirroring through Giga port on C6509. I did put ALL VLANS on its port for mirroring but I can't look at anyting vlans data. When I did set up it on Ethernet port, I can see ALL Vlans.

The giga port is connected with an optical converter and the converter is connected with NAC(Network Access Control)server.

And, I have some issue one more on the switch. When I've changed with dot1q for mirroring, it is not change.

The next is the result.

IS_Cat6509-SW> (enable) sh trunk

* - indicates vtp domain mismatch

# - indicates dot1q-all-tagged enabled on the port

$ - indicates non-default dot1q-ethertype value

Port Mode Encapsulation Status Native vlan

-------- ----------- ------------- ------------ -----------

3/5 on isl trunking 4 ----------> When I changed with dot1q, the encapsulation is not change and it is still isl.

9/4 on dot1q trunking 4

15/1 nonegotiate isl trunking 1

And the next is mirroring configuration.

#switch port analyzer

set span 3-5,7-9,32,34-35 3/5 both inpkts disable learning enable multicast enable create ------> it is mirroring command.


When I change with dot1q for the encapsulation, it is not change with 'dot1q'.

I need ur help.



New Member

Re: About Mirroring for Giga port

The Switched Port Analyzer (SPAN) feature, which is sometimes called port mirroring or port monitoring, selects network traffic for analysis by a network analyzer. The network analyzer can be a Cisco SwitchProbe device or other Remote Monitoring (RMON) probe. Previously, SPAN was a relatively basic feature on the Cisco Catalyst Series switches. However, the latest releases of the Catalyst OS (CatOS) introduced great enhancements and many new possibilities that are now available to the user. This document is not intended to be an alternate configuration guide for the SPAN feature. Rather, this document is an introduction to the recent features of SPAN that have been implemented. This document answers the most common questions about SPAN, such as:

What is SPAN and how do you configure it?

What are the different features available (especially multiple, simultaneous SPAN sessions), and what software level is necessary in order to run them?

Does SPAN impact the performances of a switch?