cluster-backup-script

#!/bin/bash -x
# +-----------------------------------------------------------------------------------------+
# | Dit script bepaald welke node live is, en doet vervolgens de andere node backupen.      |
# | We doen een arping om het mac adres te bepalen en gebruiken dit om de actieve node te   |
# | En draaien een backup van de andere node (minder belasting van de fileserver en dus     |
# | beter performance van het forum.                                                        |
# +-----------------------------------------------------------------------------------------+

# Global variables:

PATH='/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin'
SCRIPT_PATH="${0}"
ARGS="${#}"
ARG1="${1}"

NODE1='1.1.1.1'
CONF1='/etc/rsnapshot/rsnapshot-data-node1.conf'

NODE2='1.1.2.2'
CONF1='/etc/rsnapshot/rsnapshot-data-node2.conf'

CLUSTERIP='1.1.1.1'


# Functions:

  # exit function
  function die()
  {
    echo "${SCRIPT_PATH}:\n${1}"
    exit 2
  }

  # Shows usage function.
  function fShowUsage()
  {
    echo "Usage: ${SCRIPT_PATH}"
    exit 0
  }

  # check for.......
  function fCheck()
  {
    # script depends on:
    [ -x /usr/bin/arping ] || die "This script depends on Arping"

    # user must be root:
    [ "$(whoami)" = root ] || die "User must be root!"

    # check for arguments:
    [ "${ARGS}" = '1' ] || fShowUsage

    return 0
  }

  # The main function.
  function fMain()
  {
   case "${ARG1}"
   in
     usage)
       fUsage
       ;;
     daily)
       fBackup "daily"
       ;;
     hourly)
       fBackup "weekly"
       ;;
     monthly)
       fBackup "monthly"
       ;;
     *)
       fUsage
       ;;
   esac

   return 0
   }

   # the backup function
   function fBackup()
   {
    # get arguments
    if [ "${1}" = 'daily' ] ; then
       BACKUP='daily'
    elif [ "${2}" = 'weekly' ]
       BACKUP='weekly'
    elif [ "${ARG1}" = 'monthly' ]
       BACKUP='monthly'
    else
       fUsage
    fi

   # get mac from first and second node:
   local MAC1="$( arping -f ${NODE1} | grep 'Unicast reply from'  | awk '{print $5}' | tr -d "[]" )"
   local MAC2="$( arping -f ${NODE2} | grep 'Unicast reply from'  | awk '{print $5}' | tr -d "[]" )"

   # get cluster node
   local CLUSTERMAC="$( arping -f ${CLUSTERIP} | grep 'Unicast reply from'  | awk '{print $5}' | tr -d "[]" )"

   # do the magic:
   if [ "${CLUSTERMAC}" = ${MAC1} ] ; then
      CONF="${CONF2}"
      NODE="${NODE2}"
   elif [ "${CLUSTERMAC}" = ${MAC2} ]
      CONF="${CONF1}"
      NODE="${NODE1}"
   fi

   # backup :
   { /usr/bin/rsnapshot -c "${CONF}" "${BACKUP}" > /dev/null 2>&1; } || die "Failed to backup ${NODE}"

   return 0
   }


 # check environment:
  fCheck

 # Start the program:
  fMain "${@}"

 # Exit with previous return code:
  exit "${?}"