Linux下 检测在使用的IP

检测192.168.100.90-192.168.100.100这些IP中有哪些是在使用的

# vi check.sh

#!/bin/bash
#Checks to see if hosts 192.168.100.90-192.168.100.100 are alive
for n in {90..100}; do
         host=192.168.100.$n
         ping -c2 $host &>/dev/null
         if [ $? = 0 ]; then
                      echo "$host is UP"
         else
                      echo "$host is DOWN"
         fi
done

# chmod 777 check.sh

# sh check.sh