How to find the port of switch base on ip address

zhendongzhang · ‎03-06-2007

Hi,All,

Do you someone may give me some guide on how to relocate the port of switch base on I know ip address?Actually this is important when I knew someone computer send out lots of traffic.

bjw · ‎03-06-2007

If you know the IP address of the suspected device;

1. Go to the default gateway (router/L3 Switch) and do a Show arp with the known IP address.

2. Arp should come back with the MAC address associated with the known IP address.

3. On the subject switch, do a show mac-address (IOS), or show cam static (CatoS). The output of these commands will show you the MAC address and Port/Interface# where that MAC address is being seen.

Jon Marshall · ‎03-06-2007

Hi

You don't say whether the switch is layer 2 or layer 3 and whether it is IOS or CatOS.

Assuming IOS.

On the layer 3 device, whether that is the switch itself or a router,

1) show arp | include "ip address" eg

NW-MSQ1-F02-CS1#sh arp | include 10.180.172.34

Internet 10.180.172.34 64 000e.d797.1a7f ARPA FastEthernet2/1

2) On the switch

sh mac-address-table address 000e.d797.1a7f

This will give you the port that the switch has registered this mac address against.

HTH

Jon

zhendongzhang · ‎03-06-2007

Thanks all,I knew now.Thanks you. Here is my step for get port on htat switch.

1.查找高流量的IP 地址

sh ip cache flow

2.根据IP 地址查switch 上的端口

sALCNshg01#ping 10.35.3.43

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 10.35.3.43, timeout is 2 seconds:

!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 1/202/1004 ms

sALCNshg01#show arp | include 10.35.3.43

Internet 10.35.3.43 0 0011.85ea.2e2d ARPA VLAN100

sALCNshg01#show mac address 0011.85ea.2e2d

Non-static Address Table:

Destination Address Address Type VLAN Destination Port

------------------- ------------ ---- --------------------

0011.85ea.2e2d Dynamic 100 FastEthernet0/41