1#!/usr/bin/perl 2# 3# Copyright (C) 2004, 2007 Internet Systems Consortium, Inc. ("ISC") 4# Copyright (C) 2000, 2001 Internet Software Consortium. 5# 6# Permission to use, copy, modify, and/or distribute this software for any 7# purpose with or without fee is hereby granted, provided that the above 8# copyright notice and this permission notice appear in all copies. 9# 10# THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH 11# REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 12# AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, 13# INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 14# LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE 15# OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 16# PERFORMANCE OF THIS SOFTWARE. 17 18# $Id: nanny.pl,v 1.11 2007/06/19 23:47:07 tbox Exp $ 19 20# A simple nanny to make sure named stays running. 21 22$pid_file_location = '/var/run/named.pid'; 23$nameserver_location = 'localhost'; 24$dig_program = 'dig'; 25$named_program = 'named'; 26 27fork() && exit(); 28 29for (;;) { 30 $pid = 0; 31 open(FILE, $pid_file_location) || goto restart; 32 $pid = <FILE>; 33 close(FILE); 34 chomp($pid); 35 36 $res = kill 0, $pid; 37 38 goto restart if ($res == 0); 39 40 $dig_command = 41 "$dig_program +short . \@$nameserver_location > /dev/null"; 42 $return = system($dig_command); 43 goto restart if ($return == 9); 44 45 sleep 30; 46 next; 47 48 restart: 49 if ($pid != 0) { 50 kill 15, $pid; 51 sleep 30; 52 } 53 system ($named_program); 54 sleep 120; 55} 56