Linux Shell script

Below shell script shows "Hard Disk Usage" on your email address on regular basis.

Step:1

Make a file & named "disk-alert" & copy below contents in it.

######################################################################

# set admin email so that you can get email

ADMIN="abc@xyz.com" (Mention Your Mail Id Here)

# set alert level 90% is default (Set Usage Level as per the need)

ALERT=90

df -H | grep -vE '^Filesystem|tmpfs|cdrom' | awk '{ print $5 " " $1 }' | while read output;

do

#echo $output

usep=$(echo $output | awk '{ print $1}' | cut -d'%' -f1 )

partition=$(echo $output | awk '{ print $2 }' )

if [ $usep -ge $ALERT ]; then

echo "Running out of space \"$partition ($usep%)\" on $(hostname) as on $(date)" |

mail -s "Alert: Almost out of disk space $usep" $ADMIN

fi

done

######################################################################

Step:2

Edit "crontab" & make below setting.

crontab -e

59 23 * * * /root/script/diskalert

Save & Exit (:wq)

Step:3

service crond start

service sendmail start

chkconfig crond on

chkconfig sendmail on

Simple Script for extract compressed file

extract () {
   if [ -f $1 ] ; then
       case $1 in
           *.tar.bz2)   tar xvjf $1    ;;
           *.tar.gz)    tar xvzf $1    ;;
           *.bz2)       bunzip2 $1     ;;
           *.rar)       unrar x $1       ;;
           *.gz)        gunzip $1      ;;
           *.tar)       tar xvf $1     ;;
           *.tbz2)      tar xvjf $1    ;;
           *.tgz)       tar xvzf $1    ;;
           *.zip)       unzip $1       ;;
           *.Z)         uncompress $1  ;;
           *.7z)        7z x $1        ;;
           *)           echo "don't know how to extract '$1'..." ;;
       esac
   else
       echo "'$1' is not a valid file!"
   fi
 }

Shell Script To Get User Input 

#!/bin/bash

echo "Shell Script To Get User Input";

while read inputline
do
what="$inputline"
echo $what;

if [ -z "${what}" ];
then
exit
fi

done 

Question: What is the broadcast address of the network 172.31.94.0/23?