WHAT IS PING COMMAND? Ping - Definition and details
It stands for Packet Internet Groper The ping command is usually used as a simple way to verify that a computer can communicate over the network with another computer or network device. The ping command operates by sending Internet Control Message Protocol (ICMP) Echo Request messages to the destination computer and waiting for a response.
hello everyone we're going to talk about one of the most widely used utilities that are used in networking
and I'm talking about the ping command
now the ping command is a simple tool
that you can use to troubleshoot
networking issues such as network
connectivity so you can use it to test
if you're connected to a local area
network or if you're even connected to
the Internet you can also use it to test
if your network interface card is
working correctly and it's also used to
test DNS issues such as name resolution
so for example let's go ahead and ping
an IP address of a host now this host
could be any network device such as a
computer server router or printer
whether it's on your local area network
or over the Internet
but in this example, we're going to ping
a server in our local area network so we
would open up a command prompt and then
we would type the word ping along with
the IP address of the server and then
press Enter
then the ping utility will send out four
data packets to the IP address of the
the server then our computer will wait for a
the response then the server will send the
data packets back to us as a reply and
these replies are called echo reply
requests and these replies inform you
about what's happening with the server
we pinged so for example if we received
a reply then that is a good sign then
that means that there is a network
connectivity between us and the server
whether that server is on your local
area network or over the Internet
so four packets were sent and then four
packets were received but if we ping the
same server and this time if we didn't
get a reply then that means that the
the server didn't reply back and it could
mean that there is no network
connectivity between our computer and
the server now this could be for several
different reasons so for example when we
ping the server and if we get a message
back that says we quest timed out the
net could mean that the server is
powered down or it could also mean that
the server is up and running
but it's using a firewall that's
blocking all ping requests
now what happens when you try and ping a
host and not all of the data packets
reply back to you so for example when
you ping a host your computer sends out
four data packets but sometimes you may
only get one two or three packets back
instead of the four that you sent out
well this is called packet loss and
packet loss can occur for several
reasons it could mean that there's
network congestion if there is a lot of
traffic on a network and the network
can't handle all that extra traffic then
data packets will get dropped or it
could also happen because of faulty
hardware such as bad cables or bad
wiring or it could be a bad network card
or bad connections or it could be a bad
a modem which is exactly what happened to
me in my case a few years ago I was
constantly lagging and just about
everything I did on the Internet
so I did a continuous ping test and I
was dropping at least one-third of my
packets fairly consistently so I
determined that it had to be my modem so
I had it replaced and it solved the
problem
or in another scenario, if we wanted to
ping a remote server on the Internet and
if we got a message that says
destination host unreachable then that
means that a route to the destination
cannot be found so it could mean that a
the router doesn't have any information on
how to route data to the destination or
it could also mean that the remote
the server is down or disconnected from the
network or it could also mean that your
the computer is not connected to a network
so let's use the ping command in a
a typical scenario so suppose someone
tells me that they don't have an
internet connection because they can't
access any web pages with their computer
which is a pretty common issue so the
The first thing I do is that I would sit at
their computer and use the pin utility
to see if in fact they are not connected
to the Internet so even before I check
their modem or router or any cable
connections the first thing I do is do a
simple ping test so I would open up a
command prompt and see if I can ping a
website such as yahoo.com now notice in
this method I'm actually pinging the
domain name yahoo.com and not its IP
address because by doing it this way I'm
also testing name resolution issues
related to DNS and also besides that I
don't have Yahoo's IP address memorized
so by pinging yahoo.com
and if the ping is successful then I
know that we are connected to the
internet because when I got a successful
reply from yahoo.com then I
automatically know that all of my
hardware such as my cables the network
card the router and the modem are all
working correctly
including my internet service provider
so now I know that the reason that this
a computer can't bring up web pages is
related to software and not hardware so
the problem is most likely with their
internet browser or it's a firewall
issue
so by doing a ping test first it saved
me a lot of time because I bypassed the
the hassle of looking around for the modem
over the router or looking at LEDs or
checking the cables or looking behind
the computer to see if a network cable
is plugged into my network card I simply
sat down and did a simple ping test so
really the only time you need to check
your hardware is if the ping was not
successful however even before you start
checking Hardware you can also use the
ping command to check other things such
as testing, if your network interface
the card is working correctly and this is
called a loopback test a loopback test
will send out signals back to your
a computer for testing purposes so at a
command prompt I would type ping and
then the loopback IP address which is
127 0.01 or you can simply type ping
localhost which does the same thing and
if the ping was successful then you can
be assured that your network card is
working properly
but if the loopback test failed then
there's a problem with your network card
now the ping command can also be used to
test DNS name resolution issues and if
you're not familiar with what DNS does
please watch my DNS video on my youtube
channel but in a nutshell DNS is what
resolves domain names to IP addresses so
as you recall earlier I did a ping test
by pinging the domain name yahoo.com
instead of its IP address and as I said
before if the ping was successful then
that means that all of my hardware is
working correctly but besides it
also verifies that DNS is working
correctly so as you can see DNS
successfully resolved and found the IP
address for yahoo.com but if we pinged
yahoo.com and we got a message that says
ping request could not find a host
yahoo.com please check the name and try
again then this could be a DNS issue
because our computer could not resolve
the domain name to an IP address so the
The next thing to do is to try and ping the
IP address instead and that's if you
already knew what the IP address was
already or if you don't like most of us
don't already you can type in an EZ IP
address to remember such as Google's DNS
The IP address which is 8.8.8.8 and if the
ping was successful this time then this
confirms it's a DNS issue because the
the computer can ping IP addresses but it
can't ping domain names so to solve this
you can try a few things you can try
flushing your DNS by typing IP config /s
at a command prompt or you may want to
check your DNS settings on your network
card configuration and it could also be
a problem with the DNS servers
themselves or it could be a problem with
your internet service provider and
finally, the ping command can also be
combined with other subcommands called
switches and switches are used to alter
the parameters of the ping utility and
you can view a full list of these
switches by typing ping forward slash
and then a question mark so thank you
all
