The ping command is used to test network connectivity, and determines the communication status by sending ICMP echo request packets and waiting for a response. When using it, open the command line tool and enter the ping target address (such as ping google.com or ping 8.8.8.8), and the system will display information such as round trip time and packet loss rate; Windows sends 4 packets by default, and Linux/macOS continues to send until interrupted. The judgment of problems can be performed in sequence: 1. ping 127.0.0.1 Check the local protocol stack; 2. ping the default gateway to check the LAN connection; 3. ping the external address to check the external network or DNS. High latency or packet loss can try restarting the router, checking the network cable, or contacting the ISP. Advanced parameters include -c (specified times), -i (set interval), Windows -n (specified times), and -t (continuous ping) for Linux/macOS. Mastering the basic usage can meet daily inspection needs.

The ping command is one of the most basic and most commonly used tools in network diagnostics, and is mainly used to test network connectivity. It determines whether communication can be done properly by sending ICMP echo request packets to the target host and waiting for a response.

Basic usage method

To use the ping command, open the command line tool (Windows is cmd or PowerShell, macOS and Linux are terminals), and enter:

 ping destination address

The destination address can be an IP address or a domain name. For example:

 ping google.com

or:

 ping 8.8.8.8

After execution, the system will continuously send data packets and display responses, including round trip time (RTT) and packet loss rate. If you see "Request timed out" or "Destination host unreachable", there may be a problem.

On Windows, 4 packets will be sent by default; on Linux/macOS it will be sent continuously until you interrupt manually (Ctrl C).

Tips for judging network problems

ping not only uses it to see if you can access the Internet, but also helps you to determine the problem in a preliminary way:

• Local network problem : ping 127.0.0.1 (loopback address) first. If it fails, it means there is a problem with the local TCP/IP protocol stack.
• Router connection problem : ping the router's default gateway (usually 192.168.0.1 or 192.168.1.1), if it fails, it may be a local LAN connection problem.
• External network access problem : Finally ping the external address, such as the aforementioned google.com or 8.8.8.8.8. If the first two steps succeed but fail here, it may be an external network connection or DNS problem.

If you find a high latency or packet loss, you can try restarting the router, checking the network cable, or contacting the ISP.

Advanced parameter usage (on demand)

The parameters supported by ping in different systems are slightly different. Here are some common options:

• -c : Specify the number of packets sent (Linux/macOS)

   ping -c 5 google.com

• -n : Specify the number of times in Windows

   ping -n 5 google.com

• -t : Continuous ping (Windows)

   ping -t google.com

• -i : Set the sending interval (Linux)

   ping -i 2 google.com (send every two seconds)

  These parameters are suitable for advanced users to conduct more detailed tests, and daily troubleshooting of problems generally does not require too complicated operations.

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  Basically all this is it. Although the ping command is simple, it is very practical in network investigation. Mastering the basic usage can save a lot of trouble.

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