How to use the command 'ping' (with examples)

The ping command is a utility used to test the reachability of a host on an IP network. It measures the round-trip time for messages sent from the originating host to a destination computer and back. This command performs the essential task of diagnosing network communication issues. It’s a crucial tool for network administrators and IT professionals for checking network connectivity and various network-related metrics.

Use case 1: Ping the specified host

Code:

ping "hostname"

Motivation:

This is the most basic use case for the ping command, where a user wants to check if a particular host (given by its hostname or IP address) is reachable over the network. This functionality is crucial when troubleshooting network issues, verifying the status of a server, or simply checking internet connectivity.

Explanation:

• ping: This is the command itself that sends packets to the specified host and waits for replies.
• "hostname": This is the target the ping command will attempt to reach. It can be a URL like google.com or an IP address like 192.168.1.1.

Example Output:

PING google.com (172.217.16.238): 56 data bytes
64 bytes from 172.217.16.238: icmp_seq=0 ttl=113 time=15.292 ms
64 bytes from 172.217.16.238: icmp_seq=1 ttl=113 time=12.310 ms
...

Use case 2: Ping a host a specific number of times

Code:

ping -c 4 "host"

Motivation:

Sometimes network diagnostics require controlled tests to avoid excessive network traffic or to conduct a specific number of probes for data consistency. Using the -c option, users can specify how many packets they wish to send.

Explanation:

• ping: Initiates the command to ping a host.
• -c 4: This option tells the ping command to limit the number of ping packets sent. In this case, it sends 4 packets.
• "host": Can be a hostname or IP address. It’s the destination we are checking for reachability.

Example Output:

PING example.com (93.184.216.34): 56 data bytes
64 bytes from 93.184.216.34: icmp_seq=0 ttl=56 time=93.170 ms
64 bytes from 93.184.216.34: icmp_seq=1 ttl=56 time=92.575 ms
64 bytes from 93.184.216.34: icmp_seq=2 ttl=56 time=93.239 ms
64 bytes from 93.184.216.34: icmp_seq=3 ttl=56 time=92.988 ms

--- example.com ping statistics ---
4 packets transmitted, 4 packets received, 0.0% packet loss

Use case 3: Ping a host, specifying the interval in seconds between requests

Code:

ping -i 2 "host"

Motivation:

Networking professionals might want to control how often packets are sent to avoid overwhelming networks, especially in high-traffic scenarios or critical network infrastructures. The -i option allows the user to specify the interval in seconds between sending each packet.

Explanation:

• ping: Initiates the command to ping.
• -i 2: This option sets the interval between sending each packet. Here, a packet is sent every two seconds.
• "host": The target host we are performing the test on.

Example Output:

PING example.com (93.184.216.34): 56 data bytes
64 bytes from 93.184.216.34: icmp_seq=0 ttl=56 time=93.170 ms
64 bytes from 93.184.216.34: icmp_seq=1 ttl=56 time=92.575 ms
(wait two seconds)
64 bytes from 93.184.216.34: icmp_seq=2 ttl=56 time=93.239 ms
(wait another two seconds)
64 bytes from 93.184.216.34: icmp_seq=3 ttl=56 time=92.988 ms
...

Use case 4: Ping a host without trying to lookup symbolic names for addresses

Code:

ping -n "host"

Motivation:

Sometimes it’s beneficial to speed up the ping tests by avoiding DNS lookup operations, especially in cases where fast diagnostics are required, or DNS issues themselves are under investigation. Using -n results in a faster test avoiding potential blocking due to DNS resolutions.

Explanation:

• ping: Command to begin network testing.
• -n: This option tells ping to output results using numeric IP addresses only, skipping any DNS lookups.
• "host": The target host, which may be specified as a domain name or IP address.

Example Output:

PING 93.184.216.34 (93.184.216.34): 56 data bytes
64 bytes from 93.184.216.34: icmp_seq=0 ttl=56 time=93.170 ms

Use case 5: Ping a host and ring the bell when a packet is received

Code:

ping -a "host"

Motivation:

For users who need auditory confirmation of network activity, especially in scenarios where continuous visual monitoring isn’t feasible, the -a option will trigger an audible alert with every packet received. This is helpful for monitoring intermittent network issues or when multitasking.

Explanation:

• ping: The command to check network reachability.
• -a: The auditory alert option which will produce a sound upon receipt of each packet, if the terminal supports it.
• "host": The target destination to receive network packets from.

Example Output:

PING example.com (93.184.216.34): 56 data bytes
64 bytes from 93.184.216.34: icmp_seq=0 ttl=56 time=93.170 ms
(beep sound)
64 bytes from 93.184.216.34: icmp_seq=1 ttl=56 time=92.575 ms
(beep sound)
...

Use case 6: Ping a host and prints the time a packet was received

Code:

ping --apple-time "host"

Motivation:

In environments where detailed timing data can aid in diagnostics and performance analyses, this Apple-specific feature offers precise timestamps for when packets are received, which is useful for log synchronization or latency measurement on Apple systems.

Explanation:

• ping: Initiates the network diagnostic command.
• --apple-time: An Apple addition that includes the timing information of when the packets are received in the output.
• "host": The destination host.

Example Output:

PING example.com (93.184.216.34): 56 data bytes
21:35:43.123456 64 bytes from 93.184.216.34: icmp_seq=0 ttl=56 time=93.170 ms
21:35:44.654321 64 bytes from 93.184.216.34: icmp_seq=1 ttl=56 time=92.575 ms
...

Conclusion:

The ping command offers versatile options for testing and verifying network connectivity. By exploring its various use cases, such as controlling the number of packets, the interval between them, skipping DNS resolution, and using auditory or timestamp options, network professionals can efficiently diagnose and ensure reliable network performance. As an indispensable tool, ping continues to be vital for maintaining network health and troubleshooting connectivity issues.