|
Borrowed from
NetFAQs
Pinging on
Mac OS X &
Mac OS X Jaguar
A Ping helps diagnose
problems with DNS configuration and IP addresses. If you have a
"connect-but-can't-browse" problem, you can diagnose the cause of it by pinging
a name address or an IP address. You can also run a traceroute to see where the
network is down.
There are two programs you
can use to ping a name address or an IP address with Mac OSX: Terminal
and Network Utility. To access these two utilities, do the following:
On the Toolbar, click
Go and select Utilities folder from the menu.
Double click the Network
Utility icon.
Pinging via the Network Utility applet:
Select the Ping
tab.
There are two ways
to ping an Internet site:
1. By name address i.e.,
www.yahoo.com, www.ebay.com, etc.
2. By IP address i.e.,
66.218.71.80, etc.
Please enter the
network address to Ping = Enter an Internet address. In this
example, we used www.yahoo.com.
When pinging a name
address you are testing the DNS configuration. As you
can see, there is a response. The IP address of yahoo.com was
returned. If this were not so, the server would have timed out.
From this response we know two things:
1. The site is there and working (in this case yahoo.com).
2. The DNS addresses are configured properly on your computer.
If there is no
response, check the DNS configuration and ensure
that the addresses are set to have nothing in there at all or to
have these two addresses: 209.210.176.8 and 209.210.176.9.
Pinging an IP Address:
When pinging an IP address
you are testing the integrity of TCP/IP. In this example, we typed
in the IP address of yahoo.com (response from the example above). As you
can see, there is a response. We now know two things:
1. The site is there and working (66.218.71.80).
2. TCP/IP on your computer is functioning properly.
If there is no response,
TCP/IP has been corrupted.
Important:
If both the DNS and the TCP/IP are functioning properly, you'll need to
check your browsers proxy settings or you may need to upgrade your browser
or possibly reinstall the browser. Try rebooting your machine to see if
that helps.
Pinging via
the Terminal applet:
You can also Ping from the
Terminal applet.
On the Toolbar, click
Go and select Utilities folder from the menu.
Double click the Terminal
icon.
To ping a name address from
the Terminal window, do the following:
[Computer:~] user%
= Enter ping www.address.com (address = the address in question)
and click the Enter key.
Important:
There needs to be a space between ping and the name address.
You'll get the same
outcome as you do with the
Network Utility.
[Computer:~] user%
= Enter ping address (address = the IP address in question) and
click the Enter key.
Important:
There needs to be a space between ping and the IP address.
You'll get the same
outcome as you do with the
Network Utility.
Running a
Traceroute from the Network Utility:
Another way of identifying
problems with browsing is by running a traceroute.
Let me give an example. Suppose
you live in a suburb of Los Angeles and you need to drive to LAX. As you drive
along, you discover that you can't get to the airport because along the freeway
there is a traffic jam or part of the freeway is under construction. The same
is true with the Internet. When you type in a Web address, there may be a host
that is down along the way, not functioning, or jammed with Internet traffic
that prevents you from getting to that address. You can know which host is down
by running a traceroute.
Tracerouting is a network
debugging utility that traces the path from source to destination. This means
that if you're running a traceroute from your ISP to Yahoo!, you will see not
only the source (you) and the destination (Yahoo!), if it's working, but also
all the intermediary hosts along the way. If one host is down along the path,
the trace route will tell you. Do the following:
On the Toolbar, click
Go and select Utilities folder from the menu.
Double click the Network
Utility icon.
Note:
You can also run a trace route from the Terminal applet.
Select the Traceroute
tab.
Please enter the
network address to trace an internet route to = enter the name
address or IP address you're trying to reach e.g., www.yahoo.com or
66.218.71.80.
The traceroute will
trace the path from source (you) to destination (the address you're
trying to reach). Each number represents a host and one hop.
The fewer hops there are, the quicker you should access the
site. The more hops there are, the greater the possibility your
browser will time out before reaching the site. If a host is down,
or for some reason inaccessible, the trace route will tell you by
timing out.
| 
