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I am testing the availability of nodes in a netwok. For that I use ping command and see whether that machine responds back.

However, if a machine is not reachable ping should show me that that "Destination host not reachable". But if it can, it should return back with the response message. But there is no message which is being received!

What does this imply? - That ping is not enabled on that particular machine but reachable on the network ?

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  • You have to make sure the end point is set to answer to ping requests. What kind of end points do you have?
    – OakNinja
    Feb 11, 2013 at 13:54

4 Answers 4

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Ping is not the best tool to be used to test the availability of a remote network. Although ping can tell you that a network is reachable and send you response times, the lack of that information does not imply that the network is down. As the saying goes, absence of evidence is not evidence of absence.

Open your browser and go to yahoo.com and intel.com. Both come up right? Try pinging Yahoo ping yahoo.com then try pinging Intel ping intel.com Intel doesnt return any ping results. Intel probably disabled ping response for security reasons, like denying ping flooding.

Another issue with ping is that people often misinterpret the results. If you are getting a long response time, people often blame the endpoint. If you are in Windows, type pathping yahoo.com and you will see a combination of traceroute and ping, which gives much better information.

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    Ping is not the best tool to be used to test the availability of a remote network. then can you suggest some other alternative tools to detect availability ?
    – Coder
    Jan 19, 2015 at 4:43
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    @VikasGoel Well, if there was a sure thing, we would all be using it. Ping is often blocked to prevent ping flooding. The best way to test a remote server is to try to use the service it is serving. Ping can only tell you if something is up, it cant tell you something is down (not without more information).
    – Keltari
    Jan 19, 2015 at 4:53
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It means that your ICMP packet (ping) was silently discarded with no response sent. That might happen for several reasons:

  • Ping is disabled on router or (more likely) end point.
  • Network is congested or misconfigured
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  • "Pinging" is enabled in my case. Wireshark also sees the ping request coming. But there is no responses!
    – McLan
    Oct 22, 2014 at 13:59
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if your on a linux machine, you could use nmap instead

nmap -sP 192.168.x.0/24

For windows, netscanner.exe is an excellent tool (with a "live display" functionality that shows you host come and go in real time)

-- EDIT --

Since netscanner is not freeware anymore, but trialware (only the first 10 results will be shown), I went looking for alternatives and I came across this free product: https://www.mitec.cz/netscan.html

This website hosts many other useful related network tools

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Do not forget that ping is a connection like any other. It must be enabled in the firewall to be accepted and there must be service that listens and sends reply.
In most cases, ping does not work because of firewall settings.
Also do not forget that normally ping returns Connection timeout.. Destination host not reachable. is returned when the IP is not within the network.

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  • "Do not forget that ping connection like any other." Yes and no. Typical traffic uses TCP or UDP over IP. ping uses the ICMP protocol which is a different beast altogether.
    – Patrick Mevzek
    Sep 5, 2018 at 15:04

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