( nw=192.168.0 ; h=1; while [ $h -lt 255 ] ; do ( ping -c2 -i 0.2 -W 0.5 -n $nw.$h & ); h=$[ $h + 1 ] ; done ) | awk '/^64 bytes.*/ { gsub( ":","" ); print $4 }' | sort -u

Poor man's nmap for a class C network from rfc1918

What do you do when nmap is not available and you want to see the hosts responding to an icmp echo request ? This one-liner will print all hosts responding with their ipv4 address.

3
2009-06-07 15:14:46

These Might Interest You

  • This is helpful if you connect to several networks with different subnets such as 192 networks, 10 networks, etc. Cuts first three octets of ip from ifconfig command and runs nmap ping scan on that subnet. Replace wlan0 with your interface. Assumes class c network, if class b use: cut -d "." -f 1-2 and change nmap command accordingly.


    -1
    dhclient wlan0 && sbnt=$(ifconfig wlan0 |grep "inet addr" |cut -d ":" -f 2 | cut -d "." -f 1-3) && nmap $sbnt.0/24 -sP
    wltj · 2010-06-22 21:00:29 1
  • You can substitute 10.10.10.* by your own network. Or whatever nmap accepts, inlcluding submask. Show Sample Output


    0
    nmap -n -sP -oG - 10.10.10.*/32 | grep ": Up" | cut -d' ' -f2
    insaneisnotfree · 2012-08-13 15:37:21 5

  • 1
    nmap -sP 192.168.1.0/24 | grep "Nmap scan report for"| cut -d' ' -f 5 > ips.txt
    jorgemendoza · 2012-11-18 18:17:04 0
  • you need to have nmap installed sudo apt-get install nmap -y sudo yum install nmap -y Show Sample Output


    0
    nmap -sP 192.168.1.*
    narven · 2014-07-08 08:39:14 0
  • This command uses nmap to perform reverse DNS lookups on a subnet. It produces a list of IP addresses with the corresponding PTR record for a given subnet. You can enter the subnet in CDIR notation (i.e. /24 for a Class C)). You could add "--dns-servers x.x.x.x" after the "-sL" if you need the lookups to be performed on a specific DNS server. On some installations nmap needs sudo I believe. Also I hope awk is standard on most distros. Show Sample Output


    4
    nmap -R -sL 209.85.229.99/27 | awk '{if($3=="not")print"("$2") no PTR";else print$3" is "$2}' | grep '('
    netsaint · 2009-09-02 16:33:15 1
  • Depending on the network setup, you may not get the hostname. Show Sample Output


    4
    nmap 192.168.0-1.0-255 -sP
    clockworkavian · 2009-03-23 22:19:05 4

What do you think?

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