tracing switch port.

Unanswered Question
Feb 2nd, 2008

Dear All,

If have IP-address only and I want to know in which port that particular device connected.



I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 4 (1 ratings)

Mr. Naidu,

There are two commands you can take simultaneous help from.

At router do 'sho ip arp IP adress' which should give IP add to MAC binding. Note this mac address. Now you come to the switch connected to router and do 'sho mac-addres | inc MAC address', you will get the interface which either connects to the device or leads to the device through another switch. Take help of 'sho cdp ne' to identify any cisco device/switch at that port. Do the same 'sho mac-addres | inc mac address' operation on the next switch and you will ultimatelty reach to the device.

there is one more method called 'layer2 traceroute' which require mac of the device to be traced and all the swithes in between should support layer 2 tracert feature.

search google or for l2 tracert details.


ilnaiduccna Sun, 02/03/2008 - 21:08

Hi gaurav,

Thanks for your qucik respond but as you told the command 'sh mac-address | inc MAC address' giving only vlan number and again mac-adds.

AP_CS01_VJN#sh mac-address-table | include 080.421b.50c2

11 0080.421b.50c2 DYNAMIC Po1



Exactly. Now identify which cisco switch is connected to Po1 port of the AP_CS01_VJN switch. you can use 'show cdp ne' for this task. After identifying this switch telnet to it and repeat the task of 'show mac-add-------' and again look for 'sho cdp ne' for the new port. Let me know if you get the desired answer.



This Discussion