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how to configure port mirroring on a cisco 2950

Medium Priority
Last Modified: 2011-10-03

I am evaluating surfcontrol software on a windows 2003 server with sp1. The server is a member server and has 2 nics. 1 for blocking and the other for destination. In order for surfcontrol to work I configured 2 ports on a cisco 2950 switch for port mirroring. Surfcontrol does not work. So i am going back to the company today and calling surfcontrol tech support. I want to make sure that i`ve configured the switch well.
This is how i configured it:

config t
monitor session 1 source interface fastethernet 0/24
monitor session 1 destination interface fastethernet 0/23
show monitor session 1
Source Ports:
    RX Only:       None
        TX Only:       None
        Both:          Fa0/24
Destination Ports: Fa0/23

copy runn start
 Are my configs ok?

Many thanks,

Watch Question

Yeah, that looks correct.

Just make sure that fa0/24 is the port that goes out to your firewall if you have one and 0/23 is the port connected to your machine.



fa 0/24 is the source port and that is connected to 1 of the nics on the surfcontrol server. fa 0/23 is connected to the 2nd nic on the surfcontrol server. The firewall is connected to fa 0/16 on the same switch.
Am i doing this correctly,

No, the idea is to make the packets reach the surfcontrol server and have it processed. So all the outgoing packets will be going to the firewall which is fa0/16.

So you need to mirror all the traffic from fa0/16 to 0/23

By the way this will enable you to monitor the traffic but not really control it. You'll get a feel of how it works. If you want it to be doing its job, you need to make the traffic pass through the surfcontrol server or have your firewall configured for web filtering and point the web filter server's address in the firewall. This way the firewall will first consult with the surfcontrol server before it allows any http traffic. What kinda firewall ?


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It is a a 2600 cisco router.
That doesn't support what we are looking for, so you'll have to route it through the surfcontrol server itself. Just configure the span as I mentioned and call the support person.



Thank you very much!

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