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Easy Question 1

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jarcna

IS-IT--Management
Nov 23, 2006
23
US
I have switch that is in a remote location. I need to know what is connected to a specific port. I know the static IP of the device that is connected to the port that I'm looking for. Is there a command that will tell me where that device is located? Thanks.
 
Are you looking for a device like a PC plugged into a port or a directly attached Cisco device?

kumputirgeek, CHDP, Network +
 
Yes it is a device kind of like a computer. It has a NIC card, there is no GUI for this device so I can't log into and find a MAC address or anything. The switch is a 2950, this device is plugged into one of the 24 ports, I need to configure this specific port to a different VLAN as well as assign this device another IP to match this VLAN.
 
If the item has a DHCP address,

show ip dhcp snooping binding

To get the Mac address

show mac address-table

Solarwinds Engineer version (30 day demo) has a port mapper which works well. Maps all Mac per port on the switch.

MikeS

Home of the book "Network Security Using Linux"
 
It's not a DHCP address, the edge device has a static IP. I know the IP, just don't know what port it is connected too? Is there a command for that?? Thanks.
 
If the switch is not trunking and everything is in the same vlan on the switch , ping the address , look at the arp table for the mac address , then do a show mac-address command and this will tell you where that device is . If this switch is a trunked device then you would need access to the upstream layer 3 routing device to look at the arp table.
 
You need to ping the static IP from the switch, then show arp, then show mac address with the mac address obtained from the sh arp :

Example : (your device is 192.168.1.2)

#ping 192.168.1.2
#sh arp | incl 192.168.1.2
--> Internet 192.168.1.2 79 001b.a150.57c0 ARPA Vlan1
#sh mac address-table address 001b.a150.57c0
Mac Address Table
-------------------------------------------

Vlan Mac Address Type Ports
---- ----------- -------- -----
1 001b.a150.57c0 DYNAMIC Fa0/13
-->
 
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