19216811.liveATU-R130 ADSL Ethernet Router User’s Guide
Index
63
Diagnosing Problem using IP Utilities
ping
Ping
{
XE "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 you are trying to communicate with.
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
. 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 displays like that shown
in Figure .
Figure 45. Using the ping Utility
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 ATU-R130 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
{
XE "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
. A Command Prompt window displays with a bracket prompt (>). At the
prompt, type the name of the internet address your are interested in, such as www.microsoft.com.
The window will display the associate IP address, if known, as shown in Figure 1.