#!/bin/sh
str=$(ip addr | awk '/^[0-9]+: / {}; /inet.*global/ {print gensub(/(.*)\/(.*)/, "\\1", "g", $2)}')
str2=$(ip addr | awk '/^[0-9]+: / {}; /inet.*global/ {print gensub(/(.*)\/(.*)/, "\\1", "g", $2)}')
while ([[ ! "$str" =~ ^42.* ]] || [[ "$str" == "$str2" ]])
do
    dhclient -r -v eth0 && rm -f /var/lib/dhclient/* && dhclient -v eth0
    str=$(ip addr | awk '/^[0-9]+: / {}; /inet.*global/ {print gensub(/(.*)\/(.*)/, "\\1", "g", $2)}')
done
reboot