monitor command knocks out internet connection

Unanswered Question
Sep 11th, 2009
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cisco 2651XM router

IOS: c2600-adventerprisek9-mz.124-15.T9.bin

fitted with NM-16-ESW switch module on to 172.1.16.xx

I have a mail-and-web server plugged into fa1/14 on the switch module in this router, along with a PC plugged into fa1/7, and the router is connected to the internet.

I'm using monitor commands to feed traffic data on f1/4 to fa1/7 thus:

(config)#monitor session 1 source interface Fa1/14

(config)#monitor session 1 destination interface Fa1/7

The reason for this is I'm using wireshark on the PC (in f1/7) to watch traffic on the mail/web server (on f1/14) and it works great except that the monitor destination command knocks out my internet access on the PC. Without the monitor commands internet access is fine. I tried the whole thing again on a different PC and that lost the internet too so the problem is in the router.

Is there a solution to this that will give me both the traffic feed and internet access? Thanks for any help.

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Giuseppe Larosa Fri, 09/11/2009 - 13:02
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Hello Tony,

unfortunately it looks like that your only option is to add a NIC to the PC

>> . You cannot configure a SPAN destination interface to receive ingress traffic. The interface does not forward any traffic except that required for the SPAN session.

Hope to help



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