#!/bin/bash

SUBNET=192.168.2.

for i in $(seq  4);
    do echo $SUBNET$i >>ip.txt;
done
for j in $(cat ip.txt)
    #do echo $j
    do echo $j >>ip2.txt;
    ping -c 1 $j; # > /dev/null
    arp -a $j | cut -d\  -f 4 >> ip2.txt;
done