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Ping all hosts on 192.168.1.0/24

Terminal - Ping all hosts on 192.168.1.0/24
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
7
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.

Alternatives

There is 1 alternative - vote for the best!

Terminal - Alternatives
nmap -sn 192.168.1.0/24
fping -ga 192.168.1.0/24 2> /dev/null
2014-01-31 19:19:19
User: netaxiz
Tags: nmap ping
2

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

nmap -sP 192.168.0.1-254
ping -b 192.168.0.255
2014-01-27 08:06:07
User: betsubetsu
Functions: ping
Tags: ping
0

-b option takes the broadcast address.

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 26 weeks and 3 days ago

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

Comment by tankywoo 26 weeks and 2 days ago

Do you know option -b of ping?

ping -b 192.168.0.255

Comment by betsubetsu 26 weeks and 2 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.

Comment by flatcap 26 weeks and 1 day ago

Your point of view

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