systeminfo.sh

#!/bin/bash
# Menu shell script info del sistema
# Linux server / desktop.
# Define variables
LSB=/usr/bin/lsb_release
# Purpose: Display pause prompt
# $1-> Message (optional)
function pause(){
 local message="$@"
 [ -z $message ] && message="Press [Enter] key to continue..."
 read -p "$message" readEnterKey
}
# Purpose  - Display a menu on screen
function show_menu(){
    date
    echo "---------------------------"
    echo "  INFORMACION DEL SISTEMA  "
    echo "---------------------------"
 echo "1. Informacion del S.O."
 echo "2. Informacion del Hostname y dns"
 echo "3. Informacion network"
 echo "4. Usuarios conectados"
 echo "5. Ultimos usuarios conectados"
 echo "6. Informacion de la memoria"
 echo "7. Salir"
}
# Purpose - Display header message
# $1 - message
function write_header(){
 local h="$@"
 echo "---------------------------------------------------------------"
 echo "     ${h}"
 echo "---------------------------------------------------------------"
}
# Purpose - Get info about your operating system
function os_info(){
 write_header " System information "
 echo "Operating system : $(uname)"
 [ -x $LSB ] && $LSB -a || echo "$LSB command is not insalled (set \$LSB variable)"
 #pause "Press [Enter] key to continue..."
 pause
}
# Purpose - Get info about host such as dns, IP, and hostname
function host_info(){
 local dnsips=$(sed -e '/^$/d' /etc/resolv.conf | awk '{if (tolower($1)=="nameserver") print $2}')
 write_header " Hostname and DNS information "
 echo "Hostname : $(hostname -s)"
 echo "DNS domain : $(hostname -d)"
 echo "Fully qualified domain name : $(hostname -f)"
 echo "Network address (IP) :  $(hostname -i)"
 echo "DNS name servers (DNS IP) : ${dnsips}"
 pause
}
# Purpose - Network inferface and routing info
function net_info(){
 devices=$(netstat -i | cut -d" " -f1 | egrep -v "^Kernel|Iface|lo")
 write_header " Network information "
 echo "Total network interfaces found : $(wc -w <<<${devices})"
 echo "*** IP Addresses Information ***"
 ip -4 address show
 echo "***********************"
 echo "*** Network routing ***"
 echo "***********************"
 netstat -nr
 echo "**************************************"
 echo "*** Interface traffic information ***"
 echo "**************************************"
 netstat -i
 pause 
}
# Purpose - Display a list of users currently logged on 
#           display a list of receltly loggged in users   
function user_info(){
 local cmd="$1"
 case "$cmd" in 
  who) write_header " Who is online "; who -H; pause ;;
  last) write_header " List of last logged in users "; last ; pause ;;
 esac 
}
# Purpose - Display used and free memory info
function mem_info(){
 write_header " Free and used memory "
 free -m
    
    echo "*********************************"
 echo "*** Virtual memory statistics ***"
    echo "*********************************"
 vmstat
    echo "***********************************"
 echo "*** Top 5 memory eating process ***"
    echo "***********************************" 
 ps auxf | sort -nr -k 4 | head -5 
 pause
}
# Purpose - Get input via the keyboard and make a decision using case..esac 
function read_input(){
 local c
 read -p "Enter your choice [ 1 - 7 ] " c
 case $c in
  1) os_info ;;
  2) host_info ;;
  3) net_info ;;
  4) user_info "who" ;;
  5) user_info "last" ;;
  6) mem_info ;;
  7) echo "Bye!"; exit 0 ;;
  *) 
   echo "Please select between 1 to 7 choice only."
   pause
 esac
}
# ignore CTRL+C, CTRL+Z and quit singles using the trap
trap '' SIGINT SIGQUIT SIGTSTP
# main logic
while true
do
 clear
  show_menu # display memu
  read_input  # wait for user input
done