Are you on a Cisco Network – and need to know just what switch and port you are on?
try the cdpr tool – First download and install fink
Then visit monkeymetal.com
and get the latest tarball of the cdpr source.
Change the Makefile line for CDFLAGS to look like this:
CFLAGS = -Wall -ggdb -lpcap -I/sw/include
Then run make.
If it compiles all is well and run as follows…
sudo ./cdpr (Or if you copy the cdpr into a dir in your path just plain “sudo cdpr”.)
When it launches cdpr will ask what ethernet interface to look at.
If all is well it will return the DEVICE ID of the switch you are connected to, and its IP AND its port ID.
The cdpr utility can be very useful when central IT doesn’t know where everything is connected.
Good Luck!
by 
here is an update – slightly more clear version – – – –
every now and then – I lose something… really – I do… but this new baby
helps to get me back on track….
CDPR – Cisco Discovery Protocol Reporter
a tool to query the network and respond with what switch and port you are
plugged into…
never again will i lose an office or computer … I can "always" know just where
things are plugged in now…
On Windows –
You will need the winpcap libraries
http://winpcap.polito.it/install/default.htm
the windows Binaries for older versions are here
http://www.sourceforge.net/projects/cdpr
On OSX –
You will need to have the Dev Tools installed
and to make life easy – get fink
have fink install libpcap and libpcap-shlibs
then get the latest tarball from http://www.sourceforge.net/projects/cdpr or
from the home site of the project http://www.monkeymental.com/nuke/
index.php
untar the package – and make one change to the Makefile
change the CDFLAGS line to read
CFLAGS = -Wall -ggdb -lpcap -I/sw/include
this assumes that you have fink installed in "/sw" (the default for fink)
at that point "make" it.
—–
Running the Beastie!
on the mac it must run as a privileged account (ala – sudo cdpr)
on the PC – from a CMD window – just run it
c:\cdpr>cdpr<enter>
——
on the Mac – the output looks like this
dragontooth:~/Documents/builds/cdpr-2.2.0 rmleonard$ sudo ./cdpr
cdpr – Cisco Discovery Protocol Reporter
Version 2.2.0
Copyright (c) 2002-2004 – MonkeyMental.com
1. en0 (No description available)
2. lo0 (No description available)
Enter the interface number (1-2):1
Using Device: en0
Waiting for CDP advertisement:
(default config is to transmit CDP packets every 60 seconds)
Device ID
value: cpp-005-1c1.csupomona.net
Addresses
value: 134.71.198.111
Port ID
value: GigabitEthernet0/2
dragontooth:~/Documents/builds/cdpr-2.2.0 rmleonard$
so this machine is plugged into GB0/2 on 1c1 in Building 5
Ain’t life grand – I am putting this on my diagnostic laptops as we speak