Shell Programming and Scripting

#!/bin/bash

#reads input from the keyboard to populate variable "filename"
echo 'Enter file name:'
read filename

#Reads the file line by line and prints the third field which is the device name.
#Device names are saved to the file convert.txt then the entire file is moved back to the orginal file
#Leaving a clean file of just device names
# cat $filename | awk '{print $3}' >>convert.txt && mv convert.txt $filename

#Reads the device names from the now clean file one line at a time and stores the device name as variable  "ipaddr"
for ipaddr in `cat $filename`;

#This loop will ping each device name and print out on the screen is the device is up or down

do
count=$(ping -c4 $ipaddr | grep received |  awk -F',' '{ print $2 }' | awk '{ print $1 }')
if [ $count -eq 0 ]; then
  echo "Host : $ipaddr is down (ping failed) at $(date)"
else  echo "Host : $ipaddr is up"
fi
done;

mydate=$(date)

while read ipaddr
do
  count=$(ping -c4 $ipaddr | awk -F"[ ,]" '/received/{print $2}')
  if [ $count -eq 0 ]; then
    echo "Host : $ipaddr is down (ping failed) at $mydate"
  else
    echo "Host : $ipaddr is up"
fi
done < $filename

#!/usr/bin/env ruby -w
require 'net/ping'
File.readlines("file").each do |line|
   device=line.split.at(2)
   pt = Net::Ping::External.new(device)
   puts pt.ping?(device) ? "#{device} is up " : "#{device} is down "
end

#!/bin/bash

# Max concurrent job process
MAXJOBS=60

trap "kill 0" EXIT

IPLIST=($(cat))

index=0
index_count=${#IPLIST[@]}

function doping {
    local ipad=$1
    if [ -n "$ipad" ] ; then
        ping -c4 -q $ipad &>/dev/null
        [ $? -eq 0 ] && echo "Host : $ipad is up" || echo "Host : $ipad is down"
    fi
}

while [[ $index -le $index_count ]]
do
  # The current ip
  IPADDR=${IPLIST[$index]}

  NBJOBS=$(jobs -p | wc -l)
  if [ "$NBJOBS" -lt "$MAXJOBS" ] ; then

      doping $IPADDR &
      ((index++))
      continue

  fi
done
wait