network rollback script for centos 7 (with ovs)

net-rollback.sh

#!/bin/bash
netscripts="/etc/sysconfig/network-scripts"
netlock="/var/spool/network-restore.lck"
logfile="/var/log/net-rollback.log"
check_ip="8.8.8.8"

log () {
   echo $1 >&2
   echo "`date -u` - $1" >> $logfile
}


sh -c 'ping -c 5 '$check_ip' -q  > /dev/null 2>&1'

if [ "$?" != "0" ]; then
  log "public network is unreachable"
  if [  -f $netlock ]; then
    log "lock file exists - nothing will be touched till network restore"
    exit 2
  fi
  log "moving current configuration to $netscripts/ifcfg-eth0.new"
  mv $netscripts/ifcfg-eth0 $netscripts/ifcfg-eth0.new
  log "restoring old configuration to $netscripts/ifcfg-eth0"
  mv $netscripts/ifcfg-eth0.bck $netscripts/ifcfg-eth0
  log "reset ovs conf db"
  rm -rf /var/log/openvswitch/*
  rm -rf /etc/openvswitch/conf.db
  log "restarting ovs"
  systemctl restart openvswitch
  sleep 5
  log "restarting network"
  systemctl restart network
  sleep 5
  sh -c 'ping -c 5 '$check_ip' -q  > /dev/null 2>&1'
  if [ "$?" != "0" ]; then
    log "network recover didn't work and machine is isolated!"
    touch $netlock
  else
    log "network restored and public internet reachable"
  fi
else
 if [  ! -f $netscripts/ifcfg-eth0.bck ]; then
   log "machine reaches public network and a backup conf is taken"
   cp $netscripts/ifcfg-eth0 $netscripts/ifcfg-eth0.bck
 fi
 if [  -f $netlock ]; then
   log "lock file is no more needed and will be deleted"
   rm -f $netlock
 fi
fi