# Backup and replace old firewall:
cd /etc/rc.d
[ -f rc.firewall ] && mv -f rc.firewall rc.firewall.old
rm -rf rc.firewall
ln -sf /sbin/firehol rc.firewall

# If there's no config file, cp client-all.conf as default:
cd /etc/firehol
[ -e firehol.conf ] || cp examples/client-all.conf firehol.conf
chmod 640 firehol.conf