#!/bin/bash
#
# 01-01 Pete Nesbitt
# problem with interface 0, loses IP address periodicly
# script to check eth0 is up, then for a valid IP.
#
# NOTE: I also edited network script to restart firewall.
#       Otherwise need to start ipchains after calls to start network within this script.

# already have a "emailnotice" alias in /etc/aliases
DATE=`date`

# set variables for email to false
ALERT=0
LALERT=0

# another file holds the previous IP
OLDIP="/root/cronjobs/oldip"

# check that the link is up, if it is up, the following will be a non-empty file
LSTAT="`/sbin/ifconfig -a|grep -A 3 eth0|grep UP`"
if [ -z "$LSTAT" ]; then
  while [ -z "$LSTAT" ]
  do
   /etc/rc.d/init.d/network restart
   LSTAT="`/sbin/ifconfig -a|grep -A 3 eth0|grep UP`"
   LALERT=`echo "$LALERT + 1" | bc`
  done 
 echo "The external interface was DOWN, it was restarted at $DATE after $LALERT tries."|mail -s "Restarted Interface" emailnotice
fi

# check for valid IP address in ifconfig
# if line 2 has the string adr, then there will be an IP
STATUS="`/sbin/ifconfig -a|grep -A 2 eth0|grep inet`"
if [ -z "$STATUS" ]; then
  while [ -z "$STATUS" ]
  do
    /etc/rc.d/init.d/network restart
    STATUS="`/sbin/ifconfig -a|grep -A 2 eth0|grep inet`"
    ALERT=`echo "$ALERT + 1" | bc`
    NEWIP="`/sbin/ifconfig -a|grep -A 2 eth0|awk '/inet/ { print $2 }'|sed -e s/addr://`"
  done
 echo "The IP was reset at $DATE after $ALERT times, the new IP address is $NEWIP the last IP was `cat $OLDIP`"|mail -s "Lost IP" emailnotice
 echo "$NEWIP">$OLDIP
fi
exit