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2011-03-12 - Confoo 2011 presentation
Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
2011-01-04 - Moderation now required for new commands
To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.




Commands using ping from sorted by
Terminal - Commands using ping - 65 results
Mac OSX: ping -oc 30 > /dev/null && say "Google name server is up" || say "This host is down"
2014-08-01 15:44:57
User: raulyca
Functions: ping
Tags: ping beep

Audio acknowledgement for host availability.

When running the command from a Linux systems, you can use "festival" or "espeak" instead of "say".

ping -c 3 google.com
mco ping | head -n -4 | awk '{print $1}' | sort
alias alive='(while true; do ping -c 4 > /dev/null 2>&1 ; sleep 300 ; done)'
2014-06-13 06:13:57
User: DarkXDroid
Functions: alias ping sleep

Everytime You Run Bash It Will Run And Send The Command To Background In A Loop Forever. This Is Useful In Android To Avoid Getting Discconnected While Using ADB Or Other Services Like SSH By Being Inactive For Long Periods Of Time. In My Case I Get Bash Full Suport Only Through ADB And Also A Decent Python Interpreter Using Python For Android.

10,30,50 * * * * ping -c1 -w3 www.test.com >/dev/null
10,30,50 * * * * ping -q -c1 -w3 www.test.com | grep '1 received' - || mail -ne -s'Host not reachable' test@gmail.com
(prefix="10.59.21" && for i in `seq 254`; do (sleep 0.5 && ping -c1 -w1 $prefix.$i &> /dev/null && arp -n | awk ' /'$prefix'.'$i' / { print $1 " " $3 } ') & done; wait)
2014-04-02 11:20:57
User: smoky
Functions: arp awk ping sleep
Tags: ping

Waits for all pings to complete and returns ip with mac address

for i in {0..255} ; do (ping 192.168.1.$i -c 1 > /dev/null && echo "192.168.1.$i" & ) ; done
2014-01-26 18:31:34
User: bugmenot
Functions: echo ping

Pings all the hosts on in parallel, so it is very fast. Alive host IP addresses are echoed to stdout as pings are responded to.

while [ 1 ]; do (ping -c 1 google.com || growlnotify -m 'ur wifiz, it has teh sad'); sleep 10; done
ping xxx.xxx.xxx.xxx size 1024 repeat 100000
while true; do (date | tr "\n" ";") && ping -q -c 1 www.google.com|tail -1|cut -d/ -f5 ;sleep 1; done >> uptime.csv
2013-02-06 22:06:09
User: fanchok
Functions: cut date ping sleep tail tr

Used in OS X.

tr "\n" ";"

may be replaced by

echo ";"

with linux versions of date.

I reused

ping -q -c 1 www.google.com|tail -1|cut -d/ -f5

for host in $HOSTNAMES; do ping -q -c3 $host && ssh $host 'command' & for count in {1..15}; do sleep 1; jobs | wc -l | grep -q ^0\$ && continue; done; kill %1; done &>/dev/null
for host in $MYHOSTS; do ping -q -c3 $H 2>&1 1>/dev/null && ssh -o 'AllowedAuthe ntications publickey' $host 'command1; command2' & for count in 1 2 3 4 5; do sleep 1; jobs | wc -l | grep -q ^0\$ && continue; done; kill %1; done
2012-11-13 23:12:27
User: a8ksh4
Functions: grep host jobs kill ping sleep ssh wc

Execute commands serially on a list of hosts. Each ssh connection is made in the background so that if, after five seconds, it hasn't closed, it will be killed and the script will go on to the next system.

Maybe there's an easier way to set a timeout in the ssh options...

c:\>for %t in (0 1 2 3 4 5 6 7) do for %d in (0 1 2 3 4 5 6 7 8 9) do ping -n 1 machine-0%t%d
2012-09-18 03:31:52
User: bugmagnet
Functions: ping
Tags: windows cmd

%t are tens. %d are digits. One may have further outer loops to provide hundreds, thousands, etc.

This example applies ping to the numbered machines. The pattern can be used in other ways to apply all combinations of components to a task.

# ping -c 1000 -i 0.001 <host>
ping g.co|perl -ne'$|=/e=(\S+)/||next;(push@_,$1)>30&&shift@_;print"\r",(map{"\xe2\x96".chr(128+7*$_/(sort{$b<=>$a}@_)[0])." "}@_),"$1ms"'
2012-07-06 22:42:06
User: bartgrantham
Functions: perl ping

Nasty perl one-liner that provides a sparkline of ping times. If you want a different history than the last 30, just put that value in. It (ab)uses unicode to draw the bars, inspired by https://github.com/joemiller/spark-ping . It's not the most bug-free piece of code, but what it lacks in robustness it makes up for in capability. :)

If anyone has any ideas on how to make it more compact or better, I'd love to hear them.

I included a ping to google in the command just as an example (and burned up 10 chars doing it!). You should use it with: $ ping example.com | $SPARKLINE_PING_COMMAND

ping -b <broadcast address>
2012-05-21 16:55:33
User: OutputLogic
Functions: ping
Tags: ping broadcast

A simple way to find all machines on a network subnet is pinging a broadcast address (-b flag). First run ifconfig ifconfig. Then use "Bcast" address and '-b' flag in ping

pktsize=1516;for i in $( seq $pktsize -8 1450 ) ; do ping -M do -s $i -c 1 slashdot.org; done
2012-02-21 01:58:07
Functions: ping seq

Linux - starting with a packetsize that must be split into two packets, count down by 8 bytes, and try to send the packet using the "Don't Fragment" option. The actual MTU (the size of the actual PING packet) is (in this example) 1460 data bytes + 20 bytes IP header + 8 bytes PING request = 1488

for i in {1..30}; do ping -t $i -c 1 google.com; done | grep "Time to live exceeded"
2012-02-19 13:37:04
User: fossilet
Functions: grep ping

This command uses ping to get the routers' IP addresses to the destination host as traceroute does. If you know what I mean..

echo -n "IP Address or Machine Name: "; read IP; ping -c 1 -q $IP >/dev/null 2>&1 && echo -e "\e[00;32mOnline\e[00m" || echo -e "\e[00;31mOffline\e[00m"
2012-02-09 07:00:03
User: crlf
Functions: echo ping read
Tags: bash echo IP ping

I have used single packet, and in a silent mode with no display of ping stats. This is with color and UI improvement to the http://www.commandlinefu.com/commands/view/10220/check-if-a-machine-is-online. It is as per the enhancements suggested.

ping -c 1 -q MACHINE_IP_OR_NAME >/dev/null 2>&1 && echo ONLINE || echo OFFLINE
2012-02-09 06:30:55
User: UnixNeko
Functions: echo ping
Tags: echo IP ping



c 1 limits to 1 pinging attempt

q makes the command quiet (or silent mode)

/dev/null 2>&1 is to remove the display

&& echo ONLINE is executed if previous command is successful (return value 0)

|| echo OFFLINE is executed otherwise (return value of 1 if unreachable or 2 if you're offline yourself).

I personally use this command as an alias with a predefined machine name but there are at least 2 improvements that may be done.

Asking for the machine name or IP

Escaping the output so that it displays ONLINE in green and OFFLINE in red (for instance).

10,30,50 * * * * ping -c1 -w3 >/dev/null
2012-02-06 14:54:15
User: bashrc
Functions: ping

Cleaner with a mailto assignment in crontab (if the command fails you get an email):


10,30,50 * * * * ping -q -c1 -w3 >/dev/null

10,30,50 * * * * ping -q -c1 -w3 | grep '1 received' - || mail -ne -s'Host not reachable' admin@example.com
2012-02-06 10:42:46
User: knoppix5
Functions: grep mail ping

Every 20 minutes test if host with IP is 'dead' or not reachable.

The line should be put in your crontab file.

10,30,50 * * * * ping -q -c1 -w3 | grep '1 received' - || env DISPLAY=:0 xeyes
2012-02-06 09:40:11
User: knoppix5
Functions: env grep ping
Tags: ping host crontab

Every 20 minutes ping host with IP address If it's not 'alive' or not reachable, then display something eye-catching (here xeyes) on the desktop.

Hint for newbies: edit crontab with

crontab -e
ping -qc 10 server.tld | awk -F/ '/^rtt/ {print $5}'
2011-10-12 21:07:06
User: atoponce
Functions: awk ping
Tags: awk ping

Quick and dirty one-liner to get the average ping(1) time from a server.