#!/usr/bin/perl

#

# Copyright (C) Internet Systems Consortium, Inc. ("ISC")

#

# This Source Code Form is subject to the terms of the Mozilla Public

# License, v. 2.0. If a copy of the MPL was not distributed with this

# file, You can obtain one at http://mozilla.org/MPL/2.0/.

#

# See the COPYRIGHT file distributed with this work for additional

# information regarding copyright ownership.

# A simple nanny to make sure named stays running.

$pid_file_location = '/var/run/named.pid';

$nameserver_location = 'localhost';

$dig_program = 'dig';

$named_program =  'named';

fork() && exit();

for (;;) {

	$pid = 0;

	open(FILE, $pid_file_location) || goto restart;

	$pid = <FILE>;

	close(FILE);

	chomp($pid);

	$res = kill 0, $pid;

	goto restart if ($res == 0);

	$dig_command =

	       "$dig_program +short . \@$nameserver_location > /dev/null";

	$return = system($dig_command);

	goto restart if ($return == 9);

	sleep 30;

	next;

 restart:

	if ($pid != 0) {

		kill 15, $pid;

		sleep 30;

	}

	system ($named_program);

	sleep 120;

}