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Tracing a host through the layers, stuck at Trunk Port MAC

Unanswered Question
Feb 15th, 2012
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I'm trying to trace a host and I'm getting stuck at the port channel mac addresses. I need to find out where the server is connected to and the switch it lives on.

Please read below:

Step 1) Log into the core (MSFC):

r3#sh ip arp
Protocol  Address          Age (min)  Hardware Addr   Type   Interface
Internet         88   000b.453c.63fc  ARPA   Vlan732

Step 2) Grab the mac and log into the switch module:

s1> (enable) sh cam 000b.453c.63fc
* = Static Entry. + = Permanent Entry. # = System Entry. R = Router Entry.
X = Port Security Entry $ = Dot1x Security Entry

VLAN Dest MAC/Route Des [CoS] Destination Ports or VCs / [Protocol Type]

722 00-0b-45-3c-63-fc 1/1,2/1 [ALL]
732 00-0b-45-3c-63-fc 1/1,2/1 [ALL]

Step 3) Find the trunk via cdp

Port (Our Port): 1/1

Device-ID: SMG0641A041(s2)


Port (Our Port): 2/1

Device-ID: SMG0641A041(s2)

Step 4) Log into Switch 2, discover the arp points to the S2 sup engine:

732   00-0b-45-3c-63-fc         15/1

Step 5) Check the cdp nei relationship on s2 -

15/1     r4p-lnsomnptc                   Vlan1                     cisco MSFC2

How do I find out where this physical server lives? I keep getting the mac for the trunk ports which is being used for all VLANs.


The server is hanging off some switch but I need to track it down to the last end.



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Overall Rating: 0 (0 ratings)
Mandlenkosi Nkiwane Thu, 02/16/2012 - 11:11
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Have you tried to do a show mac-addr table  | i from the sup?


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