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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
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Ping all hosts on

Terminal - Ping all hosts on
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
Ping all hosts on

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.


There are 9 alternatives - vote for the best!

Terminal - Alternatives
nmap -sn
fping -ga 2> /dev/null
2014-01-31 19:19:19
User: netaxiz
Tags: nmap ping

Will report back IP address's of all hosts that are UP.

Know a better way?

If you can do better, submit your command here.

What others think

You can shorten the command a little (by removing the duplication):

for i in 192.168.1.{1..254} ; do (ping $i -c 1 > /dev/null && echo $i &); done

I've also shortened the range to: 1-254.

Addresses .0 and .255 usually have special meanings (i.e. they're not hosts).

Comment by flatcap 122 weeks ago

In "echo "192.168.1.$i" &", what is the purpose of "&" symbol in the end?

Comment by tankywoo 122 weeks ago

Do you know option -b of ping?

ping -b

Comment by betsubetsu 122 weeks ago


The brackets: (ping && echo) put the command in a subshell and the & puts the subshell in the background.

This means it can run 254 pings in a fraction of a second.

Comment by flatcap 121 weeks and 5 days ago

dobro je

Comment by sajo 46 weeks and 3 days ago

Your point of view

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