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List alive hosts in specific subnet

Terminal - List alive hosts in specific subnet
nmap -sP 192.168.1.0/24
2010-06-05 14:48:37
User: sdadh01
21
List alive hosts in specific subnet

Works on any machine with nmap installed. Previous version does not work on machines without "seq".

Also works on subnets of any size.

Alternatives

There are 5 alternatives - vote for the best!

Terminal - Alternatives
for ip in `seq 1 255`; do ping -c 1 192.168.1.$ip ; done | grep ttl
for i in 192.168.1.{1..254} ; do if ping -c1 -w1 $i &>/dev/null; then echo $i alive; fi; done

Know a better way?

If you can do better, submit your command here.

What others think

The nmap command above will work, but can go a lot faster if you don't have to do DNS lookups for each of the IP's.

Ex.:

nmap -sP -n 192.168.1.0/24

On my network, the original command takes 14.176 seconds, while the second takes 3.812.

Comment by jaymcjay 261 weeks ago

you won't find nmap on every Linux system. Forget it when you're on an older UNIX system. Yall' shouldn't diss the 'for loop' version just for being 'too long'. It sometimes come in handy.

Comment by unefunge 240 weeks and 6 days ago

Your point of view

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