plugins-scripts/check_netdns.pl

   1 #!/usr/bin/perl -w
   2
   3 # Perl version of check_dns plugin which calls DNS directly instead of
   4 # relying on nslookup (which has bugs)
   5 #
   6 # Copyright 2000, virCIO, LLP
   7 #
   8 # $Log$
   9 # Revision 1.3  2002/05/07 05:35:49  sghosh
  10 # 2nd fix for ePN
  11 #
  12 # Revision 1.2  2002/05/02 16:43:29  sghosh
  13 # fix for embedded perl
  14 #
  15 # Revision 1.1.1.1  2002/02/28 06:43:00  egalstad
  16 # Initial import of existing plugin code
  17 #
  18 # Revision 1.1  2000/08/03 20:41:12  karldebisschop
  19 # rename to avoid conflict when installing
  20 #
  21 # Revision 1.1  2000/08/03 19:27:08  karldebisschop
  22 # use Net::DNS to check name server
  23 #
  24 # Revision 1.1  2000/07/20 19:09:13  cwg
  25 # All the pieces needed to use my version of check_dns.
  26 #
  27 #
  28
  29 use Getopt::Long;
  30 use Net::DNS;
  31 use lib utils.pm;
  32 use utils ;
  33
  34 my $PROGNAME = "check_netdns";
  35
  36 Getopt::Long::Configure(`bundling`);
  37 GetOptions("V" => $opt_V,         "version" => $opt_V,
  38                                          "h" => $opt_h,         "help" => $opt_h,
  39                                          "t=i" => $opt_t,       "timeout=i" => $opt_t,
  40                                          "s=s" => $opt_s,       "server=s" => $opt_s,
  41                                          "H=s" => $opt_H,       "hostname=s" => $opt_H);
  42
  43 # -h means display verbose help screen
  44 if($opt_h){ print_help(); exit 0; }
  45
  46 # -V means display version number
  47 if ($opt_V) { print_version(); exit 0; }
  48
  49 # -H means host name
  50 $opt_H = shift unless ($opt_H);
  51 unless ($opt_H) { print_usage(); exit -1; }
  52 if ($opt_H &&
  53                 $opt_H =~ m/^([0-9]+.[0-9]+.[0-9]+.[0-9]+|[a-zA-Z][-a-zA-Z0]+(.[a-zA-Z][-a-zA-Z0]+)*)$/)
  54 {
  55         $host = $1;
  56 } else {
  57         print "$opt_H is not a valid host name";
  58         exit -1;
  59 }
  60
  61 # -s means server name
  62 $opt_s = shift unless ($opt_s);
  63 if ($opt_s) {
  64         if ($opt_s =~ m/^([0-9]+.[0-9]+.[0-9]+.[0-9]+|[a-zA-Z][-a-zA-Z0]+(.[a-zA-Z][-a-zA-Z0]+)*)$/)
  65         {
  66                 $server = $1;
  67         } else {
  68                 print "$opt_s is not a valid host name";
  69                 exit -1;
  70         }
  71 }
  72
  73 # -t means timeout
  74 my $timeout = 10 unless ($opt_t);
  75
  76 my $res = new Net::DNS::Resolver;
  77 #$res->debug(1);
  78 if ($server) {
  79         $res->nameservers($server);
  80 }
  81
  82 $res->tcp_timeout($timeout);
  83 $SIG{ALRM} = &catch_alarm;
  84 alarm($timeout);
  85
  86 $query = $res->query($host);
  87 if ($query) {
  88         my @answer = $query->answer;
  89         if (@answer) {
  90                 print join(`/`, map {
  91                         $_->type . ` ` . $_->rdatastr;
  92                 } @answer);
  93                 exit 0;
  94         } else {
  95                 print "empty answer";
  96                 exit 2;
  97         }
  98 }
  99 else {
 100         print "query failed: ", $res->errorstring, "";
 101         exit 2;
 102 }
 103
 104 sub catch_alarm {
 105         print "query timed out";
 106         exit 2;
 107 }
 108
 109 sub print_version () {
 110         my $arg0 =  $0;
 111         chomp $arg0;
 112         print "$arg0                        version 0.1";
 113 }
 114 sub print_help() {
 115         print_version();
 116         print "";
 117         print "Check if a nameserver can resolve a given hostname.";
 118         print "";
 119         print_usage();
 120         print "";
 121         print "-H, --hostname=HOST";
 122         print "   The name or address you want to query";
 123         print "-s, --server=HOST";
 124         print "   Optional DNS server you want to use for the lookup";
 125         print "-t, --timeout=INTEGER";
 126         print "   Seconds before connection times out (default: 10)";
 127         print "-h, --help";
 128         print "   Print detailed help";
 129         print "-V, --version";
 130         print "   Print version numbers and license information";
 131 }
 132
 133 sub print_usage () {
 134         my $arg0 = $0;
 135         chomp $arg0;
 136         print "$arg0 check_dns -H host [-s server] [-t timeout]";
 137         print "$arg0 [-h | --help]";
 138         print "$arg0 [-V | --version]";
 139 }
 140