So lets analyze the results that were generated by

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ping on a Linux system it will ping continuously, it won't stop until you manually tell it to do so. So let's analyze the results that were generated by the ping command. Here's the first ping packet that was sent and we received a reply from the host we sent it to, 10.0.0.3. Here's the size of the response, it was 32 bytes in size, which is what we expected. And here is some interesting information. Here's how long it took for the round trip to occur between the time we sent the ICMP echo request and the time we received the ICMP echo response from this host. This first packet took about one millisecond, that's actually really, really fast. The reason it's so fast is because these two hosts are connected to the same switch. If we did this with a host out on the internet it would take considerably longer. And then notice we received three more replies from the subsequent ICMP echo request that we sent to this host. You'll notice over here that the three that came after the first one were even faster. The round trip time was actually less than one millisecond. Most likely the reason this first one took just a little bit longer is because this host had to use the ARP protocol to determine what the MAC address was that's associated with the host that has an IP address of 10.0.0.3 and that took just a little bit of time. Once that ARP request was completed and the IP address to MAC address mapping was alreadystored in the ARP table on the system the next three requests didn't actually have to go through the ARP process. It already knew what the MAC address was for this host and so it didn't take nearly as long. Down here we can review a summary of the statistics for the ping request that were sent to 10.0.0.3. There were four packets sent and four were received. That's good. That tells us we have good connectivity between this host and the remote host 10.0.0.3. None of them were lost. And down here we can review approximate round trip times in milliseconds. The minimum was less than one millisecond, which rounded down to zero. The maximum was around one millisecond, the average being less than one millisecond. We have a good connection between this host and the host with an IP address of 10.0.0.3. Now in addition to pinging by IP address you can also ping by host name. For example, the host name of this system is fs3.nebo-tech.com. Now pinging by host name can reveal valuable information. If you're able to ping by the host IP address and it's successful but you try sending a ping to the same host but this time using its host name instead of its IP address and it doesn't work that tells you that the problem that you're having with network communications resides within your name resolution service. The actual physical connectivity and the IP configuration is working because this ping request worked just fine. If you can't ping by a host name then most likely the problem is that your DNS server is not available or isn't resolving this host name into an IP address correctly. Now on this system I believe everything should work correctly. Let's go ahead and ping this same host 10.0.0.3 by its DNS name this time, fs3.nebo-tech.com. Notice that the first thing that happens is that the host name we specified is resolved into an IP address.
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