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Passing Traffic on a SPAN Port

I am trying to set up a URL filtering product (Elron's Web Inspector) that needs to see all outbound traffic to the internet, and reply to the requester with a spoofed packet for blocked URLs. In order to monitor outbound traffic, I have to set up a SPAN port, which would block the spoofed reply packet from the URL filter. Any ideas on a workaround? My current options are to put two NICs in the Web Inspector box, or put a FastEthernet Hub (Half-Duplex) directly between the switch and internet router.

I am using native mode on a 6509.

  • Other Network Infrastructure Subjects

Re: Passing Traffic on a SPAN Port

Hi ,

Firstly what version of Web Inspector are you using. If you are using v6.x then the dual NIC feature is not supported. The older versions supported the use of two NICs one working in the prmiscuous mode and the other in the management mode. Are you going to be placing the hub as the internet gateway ... if so that could create a bottleneck . You could instead use a 3500 series switch which supports SPAN and it also supports multiple span sessions.Do not use a 2950 switch as it does not support TX traffic on the spanned port . This will be a problem if you are using WI 6.x.

Hope this helps.