Send a ping to each IP on a subnet

Is there a command line based way to send pings to each computer in a subnet? Like

for(int i = 1; i < 254; i++)
    ping(192.168.1.i);

to enforce arp resolution?

Not all machines have nmap available, but it's a wonderful tool for any network discovery, and certainly better than iterating through independent ping commands.

$ nmap -n -sP 10.0.0.0/24

Starting Nmap 4.20 ( http://insecure.org ) at 2009-02-02 07:41 CST
Host 10.0.0.1 appears to be up.
Host 10.0.0.10 appears to be up.
Host 10.0.0.104 appears to be up.
Host 10.0.0.124 appears to be up.
Host 10.0.0.125 appears to be up.
Host 10.0.0.129 appears to be up.
Nmap finished: 256 IP addresses (6 hosts up) scanned in 2.365 seconds

I would suggest the use of fping with the mask option, since you are not restricting yourself in ping.

fping -g 192.168.1.0/24

The response will be easy to parse in a script:

192.168.1.1 is alive
192.168.1.2 is alive
192.168.1.3 is alive
192.168.1.5 is alive
...
192.168.1.4 is unreachable
192.168.1.6 is unreachable
192.168.1.7 is unreachable
...

Note: Using the argument -a will restrict the output to reachable ip addresses, you may want to use it otherwise fping will also print unreachable addresses:

fping -a -g 192.168.1.0/24

From man:

> fping differs from ping in that you can specify any number of targets > on the command line, or specify a file containing the lists of targets > to ping. Instead of sending to one target until it times out or > replies, fping will send out a ping packet and move on to the next > target in a round-robin fashion.

More info: http://fping.org/

Broadcast ping:

$ ping 192.168.1.255
PING 192.168.1.255 (192.168.1.255): 56 data bytes
64 bytes from 192.168.1.154: icmp_seq=0 ttl=64 time=0.104 ms
64 bytes from 192.168.1.51: icmp_seq=0 ttl=64 time=2.058 ms (DUP!)
64 bytes from 192.168.1.151: icmp_seq=0 ttl=64 time=2.135 ms (DUP!)
...

(Add a -b option on Linux)

In Bash shell:

#!/bin/sh

COUNTER=1

while [ $COUNTER -lt 254 ]
do
   ping 192.168.1.$COUNTER -c 1
   COUNTER=$(( $COUNTER + 1 ))
done

I just came around this question, but the answers did not satisfy me. So i rolled my own:

echo $(seq 254) | xargs -P255 -I% -d" " ping -W 1 -c 1 192.168.0.% | grep -E "[0-1].*?:"

• Advantage 1: You don't need to install any additional tool
• Advantage 2: It's fast. It does everything in Parallel with a timout for every ping of 1s ("-W 1"). So it will finish in 1s :)
• Advantage 3: The output is like this

> 64 bytes from 192.168.0.16: icmp_seq=1 ttl=64 time=0.019 ms > 64 bytes from 192.168.0.12: icmp_seq=1 ttl=64 time=1.78 ms > 64 bytes from 192.168.0.21: icmp_seq=1 ttl=64 time=2.43 ms > 64 bytes from 192.168.0.1: icmp_seq=1 ttl=64 time=1.97 ms > 64 bytes from 192.168.0.11: icmp_seq=1 ttl=64 time=619 ms

Edit: And here is the same as script, for when your xargs do not have the -P flag, as is the case in openwrt (i just found out)

for i in $(seq 255);
do
 ping -W 1 -c 1 10.0.0.$i | grep 'from' &
done

The command line utility nmap can do this too:

nmap -sP 192.168.1.*

for i in $(seq 1 254); do ping -c1 -t 1 192.168.11.$i; done

Adding a -t 1 waits only one second before exiting. This improves the speed a lot if you just have a few devices connected to that subnet.

FOR /L %i in (1,1,254) DO PING 192.168.1.%i -n 1 -w 100 | for /f "tokens=3 delims=: " %j in ('find /i "TTL="') do echo %j>>IPsOnline.txt

This is a modification of @david-rodríguez-dribeas answer above, which runs all the pings in parallel (much faster) and only shows the output for ip addresses which return the ping.

export COUNTER=1
while [ $COUNTER -lt 255 ]
do
    ping $1$COUNTER -c 1 -w 400 | grep -B 1 "Lost = 0" &
    COUNTER=$(( $COUNTER + 1 ))
done

Under linux, I think ping -b 192.168.1.255 will work (192.168.1.255 is the broadcast address for 192.168.1.*) however IIRC that doesn't work under windows.

I came late but here is a little script I made for this purpose that I run in Windows PowerShell. You should be able to copy and paste it into the ISE. This will then run the arp command and save the results into a .txt file and open it in notepad.

# Declare Variables
$MyIpAddress
$MyIpAddressLast

# Declare Variable And Get User Inputs
$IpFirstThree=Read-Host 'What is the first three octects of you IP addresses please include the last period?'
$IpStart=Read-Host 'Which IP Address do you want to start with? Include NO periods.'
$IpEnd=Read-Host 'Which IP Address do you want to end with? Include NO periods.'
$SaveMyFilePath=Read-Host 'Enter the file path and name you want for the text file results.'
$PingTries=Read-Host 'Enter the number of times you want to try pinging each address.'

#Run from start ip and ping
#Run the arp -a and output the results to a text file
#Then launch notepad and open the results file
Foreach($MyIpAddressLast in $IpStart..$IpEnd)
{$MyIpAddress=$IpFirstThree+$MyIpAddressLast
    Test-Connection -computername $MyIpAddress -Count $PingTries}
arp -a | Out-File $SaveMyFilePath
notepad.exe $SaveMyFilePath

#!/bin/sh

COUNTER=$1

while [ $COUNTER -lt 254 ]
do
 echo $COUNTER
 ping -c 1 192.168.1.$COUNTER | grep 'ms'
 COUNTER=$(( $COUNTER + 1 ))
done

#specify start number like this: ./ping.sh 1
#then run another few instances to cover more ground
#aka one at 1, another at 100, another at 200
#this just finds addresses quicker. will only print ttl info when an address resolves

This Script works well in OpenWRT

In a new file put this code ,

#!/bin/sh
echo "Online IPs" > out.txt
COUNTER=1

while [ $COUNTER -lt 255 ]
do
 ping $1.$COUNTER -c 1 -w 400 | grep "time" >> out.txt &
 COUNTER=$(( $COUNTER + 1 ))
done
killall ping

Set execution permision and launch it

root@r1:/# nping 192.168.1

then view all host connected in out.txt file

for i in $(seq 1 254); do ping -c1 192.168.11.$i; done