span to PC port for silent monitoring on Cisco IP Phone 7941

Unanswered Question
Jul 19th, 2007


I have my laptop plugged into my IP Phone 7941 PC Port and was wanting to use ethereal on my laptop to examine packets been sent to the phone. Is this possible?

Using Callmanager 4.2 but in 'Phone Configuration' there is no option to set 'Span to PC Port' and this setting on the phone is set to 'No' with no option to edit it.

Any ideas?

Thanks in advance

I have this problem too.
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gogasca Sat, 07/21/2007 - 20:23

Check this bug :

CSCsg09173: No web access cfg option for 7941/61 in CCM device donfiguration


Following parameters are missing with 4.2(3)

Auto Line Select

Web Access,

Span to PC Port

Load Server

The title says no web access, but the problem of no SPAN to PC port is also fixed with this bug.

Apply Latest ES or SR and you should have the options again.

Jason Aarons Sun, 07/22/2007 - 18:15

Let me know once you have a valid Ethereal capture and attempt playback. I couldn't get Ethereal to detect the SCCP/RTP packets and playback properly. The sniff shows them there but just can't playback the audio. I'd be interesting in assisting you if needed.

Jason Aarons Sun, 07/22/2007 - 23:40

By default the 7940 spans phone packets to the PC Port. Run Ethereal/Network Monitor and you will see them -jason

bvial1989 Mon, 07/23/2007 - 14:51

Doesn't seem to span by default on our setup. We have CallManager 4.3 and 7941 phones.

I am going to try running the SR updates and see if we can get the 'Span to PC Port' back.


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