for i in {0..255} ; do (ping 192.168.1.$i -c 1 > /dev/null && echo "192.168.1.$i" & ) ; done

Ping all hosts on 192.168.1.0/24

Pings all the hosts on 192.168.1.0/24 in parallel, so it is very fast. Alive host IP addresses are echoed to stdout as pings are responded to.
Sample Output
192.168.1.5
192.168.1.10

7
By: bugmenot
2014-01-26 18:31:34

2 Alternatives + Submit Alt

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 $i &); done I've also shortened the range to: 1-254. Addresses .0 and .255 usually have special meanings (i.e. they're not hosts).
flatcap · 224 weeks and 6 days ago
In "echo "192.168.1.$i" &", what is the purpose of "&" symbol in the end?
tankywoo · 224 weeks and 6 days ago
Do you know option -b of ping? ping -b 192.168.0.255
betsubetsu · 224 weeks and 6 days ago
@tankywoo 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.
flatcap · 224 weeks and 4 days ago
dobro je
sajo · 149 weeks and 2 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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