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Display only hosts up in network

Terminal - Display only hosts up in network
nmap -sP your network/submask | awk "/^Host/"'{ print $2 }'
2009-04-02 12:41:54
User: rauhmaru
Functions: awk
Display only hosts up in network

This command will display only the hosts that are active in the network.


There are 4 alternatives - vote for the best!

Terminal - Alternatives
nmap -sP -PR -oG - `/sbin/ip -4 addr show | awk '/inet/ {print $2}' | sed 1d`
2011-07-21 11:50:26
User: l3k
Functions: awk sed

Today many hosts are blocking traditional ICMP echo replay for an "security" reason, so nmap's fast ARP scan is more usable to view all live IPv4 devices around you. Must be root for ARP scanning.

Know a better way?

If you can do better, submit your command here.

What others think

The awk bit also catches the summary line at the end as it stands. If you just want the hosts, try this:

nmap -sP your network/submask | awk "/^Host/"'{ print $2 }'
Comment by TheMightyBuzzard 317 weeks and 4 days ago

Mmmm, yes =)


Comment by rauhmaru 317 weeks and 4 days ago

Command exists in here several times. Do try a grep of the archive before posting. In your defense, I got this same message for my first post. Ironically, for this same command :-/

Also, on networks that allow named hosts (like mine), the line reads

#Host aveil ( appears to be up.

and so you would print out the machine name, not the network. Machines that don't have names, will then cause both ips and names to print out, which would look odd.

lan|grep Host |grep -oE '[0-9]+\.[0-9\.]+'

will filter out only IP addresses from such networks.

Comment by clockworkavian 317 weeks and 4 days ago

Your point of view

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