How to Use Ping Command in Linux with Examples

Ping is a simple, widely used, cross-platform networking utility for testing if a host is reachable on an Internet Protocol (IP) network. It works by sending a series of Internet Control Message Protocol (ICMP) ECHO_REQUEST messages to the target host and waiting for an ICMP echo reply (or ECHO_RESPONSE).

You can run a ping test in order to establish if your computer can communicate with another computer (target host); it helps you determine:

• Whether the target host is reachable (active) or not.
• To measure the amount of time it takes for packets to get to the target host and back to your computer (the round-trip time (rtt) in communicating with the target host) and
• The packet loss is expressed as a percentage.

Its output is a list of replies from the target host along with the time taken for the last packet to reach the target host and back to your computer.

It also shows a statistical summary of the test, typically including the number of packets transmitted and those received, the percentage of packet loss; the minimum, maximum, the mean round-trip times, and the standard deviation of the mean (mdev). In case a ping test fails, you will see error messages as output.

Ping Command Examples in Linux

In this article, we will explain 12 practical ping command examples for testing the reachability of a host on a network.

1. Ping Domain or IP Address

You can run a simple ping test to see whether the target host www.google.com is reachable or not. You can also use an IP address instead of the domain name as shown.

$ ping www.google.com
OR
$ ping 172.217.27.196

Sample Output:

ping www.google.com
PING www.google.com (172.217.27.196) 56(84) bytes of data.
64 bytes from bom07s15-in-f4.1e100.net (172.217.27.196): icmp_seq=1 ttl=111 time=5.01 ms
64 bytes from bom07s15-in-f4.1e100.net (172.217.27.196): icmp_seq=2 ttl=111 time=4.75 ms
64 bytes from bom07s15-in-f4.1e100.net (172.217.27.196): icmp_seq=3 ttl=111 time=5.37 ms
64 bytes from bom07s15-in-f4.1e100.net (172.217.27.196): icmp_seq=4 ttl=111 time=4.99 ms
^C
--- www.google.com ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3004ms
rtt min/avg/max/mdev = 4.751/5.030/5.373/0.222 ms
...

From the results of the above command, the ping was successful and there were no packets lost. One important thing to take note of, in a ping test output is the time at the end of each ping reply.

Assuming you are carrying out ping testing on your servers, then the value here matters a lot, depending on the type of application you are running on a server.

If, for example, you have a web application where a single user request results in so many queries to a database(s) to generate results on the UI, then a lower ping time to that particular server implies more data is being transmitted without a delay and the opposite is true.

2. Ping Echo Request

You can specify the number of ECHO_REQUESTs to be sent after which ping exits, using the -c flag as shown (in this case the ping test will stop after sending 5 packets).

$ ping -c 5 www.google.com

PING www.google.com (172.217.27.196) 56(84) bytes of data.
64 bytes from bom07s15-in-f4.1e100.net (172.217.27.196): icmp_seq=1 ttl=111 time=4.31 ms
64 bytes from bom07s15-in-f4.1e100.net (172.217.27.196): icmp_seq=2 ttl=111 time=4.35 ms
64 bytes from bom07s15-in-f4.1e100.net (172.217.27.196): icmp_seq=3 ttl=111 time=4.06 ms
64 bytes from bom07s15-in-f4.1e100.net (172.217.27.196): icmp_seq=4 ttl=111 time=5.20 ms
64 bytes from bom07s15-in-f4.1e100.net (172.217.27.196): icmp_seq=5 ttl=111 time=4.41 ms

--- www.google.com ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4006ms
rtt min/avg/max/mdev = 4.064/4.464/5.195/0.383 ms

3. Set Ping Interval Timeout

The -i flag allows you to set intervals in seconds between sending each packet, the default value is one second.

$ ping -i 3 -c 5 www.google.com

PING www.google.com (172.217.27.196) 56(84) bytes of data.
64 bytes from bom07s15-in-f4.1e100.net (172.217.27.196): icmp_seq=1 ttl=111 time=5.71 ms
64 bytes from bom07s15-in-f4.1e100.net (172.217.27.196): icmp_seq=2 ttl=111 time=6.19 ms
64 bytes from bom07s15-in-f4.1e100.net (172.217.27.196): icmp_seq=3 ttl=111 time=5.39 ms
64 bytes from bom07s15-in-f4.1e100.net (172.217.27.196): icmp_seq=4 ttl=111 time=7.34 ms
64 bytes from bom07s15-in-f4.1e100.net (172.217.27.196): icmp_seq=5 ttl=111 time=4.77 ms

--- www.google.com ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 12014ms
rtt min/avg/max/mdev = 4.768/5.879/7.341/0.863 ms

4. DoS Attack with Ping Flooding aka Ping of Death

To determine the response of your network under high-load conditions, you can run a “flood ping” which sends requests as fast as possible, using the -f switch. Only the root can use this option, otherwise, use the sudo command to gain root privileges.

$ sudo ping -f www.google.com
OR
$ sudo ping -f -i 3 www.google.com	#specify interval between requests 

PING www.google.com (172.217.163.36) 56(84) bytes of data.
.......................................................................................................................................................................................^C
--- www.google.com ping statistics ---
2331 packets transmitted, 2084 received, 10% packet loss, time 34095ms
rtt min/avg/max/mdev = 29.096/29.530/61.474/1.417 ms, pipe 4, ipg/ewma 14.633/29.341 ms

5. Ping Broadcast of a LAN

You can enable pinging a broadcast using the -b option, which will get a response from all IP addresses connected to your LAN network.

$ ping -b 192.168.0.0

6. Set Ping TTL Value

To limit the number of network hops (TTL – Time-to-live) that probes traverse, use the -t flag. You can set any value between 1 and 255; different operating systems set different defaults.

Each router that receives the packet subtracts at least 1 from the count and if the count is still greater than 0, the router forwards the packet to the next hop, otherwise, it discards it and sends an ICMP response back to your computer.

In this example, the TTL has been exceeded and the ping test has failed, as shown in the screenshot.

$ ping -t 10 www.google.com

7. Set Ping Packet Size

The default packet size should be sufficient for a ping test, however, you can change it to meet your specific testing needs. You can specify the size of the payload, in the number of bytes using the -s option, which will result in a total packet size of the value provided plus 8 extra bytes for the ICMP header.

$ ping -s 1000 www.google.com

8. Set Ping Preload

If preload is added, ping sends that many packets not waiting for a reply. Note that only the root may select a preload of more than 3, otherwise, use the sudo command to gain root privileges.

$ sudo ping -l 5 www.google.com 

9. Set Ping Timeout

It is also possible to set the time to wait for a response, in seconds, using the -W option as shown.

$ ping -W 10 www.google.com

10. Set Ping Timeout in Seconds

To set a timeout in seconds, before ping exits regardless of how many packets have been sent or received, use the -w flag.

$ ping -w 5 www.google.com

11. Ping Debug ICMP Packets

The -d option allows you to enable the debug IP packet detail as shown.

$ ping -d www.google.com

12. Ping Verbose Output

You can enable verbose output using the -v flag, as follows.

$ ping -v www.google.com

Note: Ping may not necessarily be used for testing networking connectivity, it simply tells you whether an IP address is active or inactive.

It is normally used together with the traceroute program, but, MTR – a modern network diagnostic tool combines the functionality of ping and traceroute and offers many additional features.

For a comprehensive list of networking tools, check out: Linux Network Management, Troubleshooting, and Debugging

Summary

Ping is a very common method for troubleshooting the accessibility of hosts on a network. In this article, we’ve explained 12 practical ping command examples for testing the reachability of a networked device. Share your thoughts with us via the comment form below.