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User’s Guide
Diagnosing Problem using IP Utilities
Ping
Ping is a command you can use to check whether your PC can recognize other computers
on your network and the Internet. A ping command sends a message to the computer you
specify. If the computer receives the message, it sends messages in reply. To use it, you
must know the IP address of the computer with which you are trying to communicate.
On Windows-based computers, you can execute a ping command from the Start menu. Click
the Start button, and then click Run. In the Open text box, type a statement such as the
following:
ping 192.168.1.1
Click OK. You can substitute any private IP address on your LAN or a public IP address for
an Internet site, if known.
If the target computer receives the message, a Command Prompt window is displayed:
If the target computer cannot be located, you will receive the message Request timed out.
Using the ping command, you can test whether the path to the device is working (using the
preconfigured default LAN IP address 192.168.1.1) or another address you assigned.
You can also test whether access to the Internet is working by typing an external address,
such as that for www.yahoo.com (216.115.108.243). If you do not know the IP address of a
particular Internet location, you can use the nslookup command, as explained in the
following section.
From most other IP-enabled operating systems, you can execute the same command at a
command prompt or through a system administration utility.
nslookup
You can use the nslookup command to determine the IP address associated with an Internet
site name. You specify the common name, and the nslookup command looks up the name in
on your DNS server (usually located with your ISP). If that name is not an entry in your ISP’s
DNS table, the request is then referred to another higher-level server, and so on, until the
entry is found. The server then returns the associated IP address.
On Windows-based computers, you can execute the nslookup command from the Start
menu. Click the Start button, and then click Run. In the Open text box, type the following:
Nslookup
Click OK. A Command Prompt window displays with a bracket prompt (>). At the prompt,
type the name of the Internet address that you are interested in, such as
www.microsoft.com.
The window will display the associate IP address, if known, as shown below:
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