The UNIX ping command lets you test network servers and latency. Here's how to use it in the macOS Terminal app.
The UNIX command is a tiny UNIX network tool that allows you to test your network, that of your ISP or organization, remote servers, and network latency.
is one of the oldest and simplest UNIX commands and is available in virtually all UNIX distributions, including macOS.
was written by the late Mike Muuss in 1983 at the US Army Defense Ballistics Lab. Sadly, Muuss died young in 2000 at the age of 42, in a car accident on Interstate 95 in Maryland.
Muuss was also the author of several 3D/CAD apps at the time, as well as the UNIX utility which measures network throughput using TCP and UDP protocols. Muuss' original technical web page is still available on one of the first fifty servers on the internet: a US Army FTP server for the Ballistics Lab.
The command works by using the Internet Control Message Protocol (ICMP) - in particular by sending packets, and by utilizing its Time To Live (TTL), latency, and packet loss detection to measure round trip hops to a given internet-connected computer at either an IP address or domain name.
Don't confuse Time To Live with a different subject from electronics: Transistor-to-transistor Logic (also abbreviated 'TTL').
The name "ping" comes from submarine SONAR technology which detects underwater vessels by emitting sound waves, and then measuring the time it takes for echoes to return.
With you can detect if your network is working, hops in between your computer and the destination, round-trip times, and whether a given computer is online or not.
If your computer has a working internet connection you'll see begin its tests, which will keep running until you stop it by pressing Command-Z on your keyboard (unless you specified the (count) option with the command).
When you use , you can specify either the IP address of the target computer or a domain name. If you use a domain, will use DNS to resolve the domain name to that domain's default server (or to a gateway or CDN that points to the default server).
You can also ping your own computer's network interface to see if the device is working properly or not.
is a quick and easy way to conduct network tests on your own network, your Mac, and on remote machines. Once you know how it works, you'll find yourself using it all the time.