An utility script to correct MAC address configs. This script recovers MAC address mismatch between actual NIC's address and system config. This may useful for copied VM(ex. VirtualBox, VMWare) image.

reset-nic-mac-addr.sh

#!/bin/bash

cat /etc/udev/rules.d/70-persistent-net.rules \
  | grep -v 'SUBSYSTEM=="net"' \
  > /tmp/net.rules
mv -f /tmp/net.rules /etc/udev/rules.d/70-persistent-net.rules

i=0
for hwaddr in $(/sbin/ifconfig -a | grep '^eth' | grep 'HWaddr' | sed 's/^.*HWaddr \([0-9A-Z:]*\).*$/\1/g'); do
  cat /etc/sysconfig/network-scripts/ifcfg-eth$i \
    | sed "s/HWADDR=.*/HWADDR=${hwaddr}/g" \
    > /tmp/ifcfg-eth$i
  mv -f /tmp/ifcfg-eth$i /etc/sysconfig/network-scripts/ifcfg-eth$i

  i=$(expr $i + 1)
done

reboot