ping - Linux

Overview

The ping command is a network utility used to test the availability of a host on an IP network. It operates by sending Internet Control Message Protocol (ICMP) Echo Request messages to the target host and listens for Echo Reply messages. Its primary use is for troubleshooting network connectivity issues and for performance measurement.

Syntax

ping [options] destination
  • destination: This can be either an IP address or a hostname to which the ICMP Echo Requests are sent.

Options/Flags

  • -a: Audible ping. Play a beep sound for each response received.
  • -c count: Stop after sending (and receiving) count ECHO_RESPONSE packets.
  • -i interval: Wait interval seconds between sending each packet. The default is 1 second.
  • -s packetsize: Specifies the number of data bytes to be sent.
  • -t ttl: Set the IP Time to Live.
  • -q: Quiet output. Only display the summary lines at startup time and when finished.
  • -l preload: Send preload number of packets as fast as possible before falling into the normal rate of sending (only as superuser).
  • -f: Flood ping. Outputs packets rapidly (only as superuser). Very high rate ping, useful for stress tests.
  • -w deadline: Specify a deadline in seconds by which the command will terminate regardless of how many packets have been sent or received.

Examples

  • Basic ping:

    ping google.com

    Sends ICMP packets to google.com until interrupted.

  • Ping with count:

    ping -c 4 google.com

    Send exactly 4 packets to google.com and then exit.

  • Specifying packet size:

    ping -s 100 google.com

    Sends packets of 100 bytes to google.com.

  • Ping with deadline:

    ping -w 10 google.com

    Continue to send packets to google.com for 10 seconds.

Common Issues

  • Permission denied: Without superuser rights, the -f (flood) option might fail.
  • Network is unreachable: Indicates a problem with the local network configuration; check your network settings and interfaces.
  • Unknown host: The DNS resolution for the destination failed; verify the hostname and DNS settings.

Integration

Combining ping with grep:

ping -c 10 example.com | grep 'bytes from'

This command pings example.com 10 times, but only outputs the lines indicating responses.

Scripting:

for ip in {1..10}; do
  ping -c 1 "192.168.0.$ip"
done

Pings 10 hosts in a local subnet and checks their availability.

  • traceroute: Trace the route packets take to a network host.
  • netstat: Display network connections, routing tables, interface statistics, and more.
  • nc (netcat): Utility for reading from and writing to network connections.

Further reading:

  • Visit Ping Man Page for more in-depth details on usage and options.