Generate_array!

while read a;
do 
        arr[x++]="${a}";
done < ip_list.txt

#arr[x]-->form -->"20  192.168.0.1"

ip_list.txt:

20  192.168.0.1

10  192.168.0.2

30  192.168.0.3

Finally:

${arr[0]}---> 20  192.168.0.1

${arr[1]}---> 10   192.168.0.2

${arr[2]}--->  30   192.168.0.3

${#arr[@]}--->3