Talk:Monitor your fax queue with Nagios

This check doesn't include a timeout which means that if the check runs for too long you can have a heap of old checks running which consume a lot of CPU. The problem cascades as the more CPU used by old checks, the more likely it is for new checks to timeout...

At least, this is the situation I encountered when running the check on remote system via check_by_ssh.

I've made the following change to include a timeout. The code was mostly pulled from check_mailq. I've only done basic testing although the change is trivial.

--- check_hylafax 2009-08-11 08:38:27.000000000 +1000 +++ check_hylafax.new 2009-08-11 08:38:39.000000000 +1000 @@ -2,7 +2,7 @@

use strict;
use Getopt::Long;

-use vars qw($opt_V $opt_h $opt_H $opt_P $opt_w $opt_c $opt_l $opt_p $PROGNAME); +use vars qw($opt_V $opt_h $opt_H $opt_P $opt_w $opt_c $opt_l $opt_p $opt_t $PROGNAME);

use lib "/usr/lib/nagios/plugins" ;
use utils qw(%ERRORS &print_revision &support &usage);
use Net::FTP;

@@ -26,6 +26,7 @@

        "P=i" => \$opt_P, "port=i" => \$opt_P,
        "l=s" => \$opt_l, "login=s" => \$opt_l,
        "p=s" => \$opt_p, "password=s" => \$opt_p,

+ "t=i" => \$opt_t, "timeout=i" => \$opt_t

);

if ($opt_V) {

@@ -41,6 +42,10 @@

my $port = ($opt_P ? $opt_P : "4559");
usage("Invalid port: $opt_P\n") unless ($port > 1 and $port < 32767);

+unless (defined $opt_t) { + $opt_t = $utils::TIMEOUT ; # default timeout +} +

usage("Warning threshold not specified\n") if not $opt_w;
my $warning = $opt_w;
usage("Invalid warning threshold: $opt_w\n") unless $warning =~ /^\d+$/;

@@ -53,6 +58,12 @@

#my $critical = $1 if ($opt_c =~ /([0-9]{1,2}|100)/);
#($critical) || usage("Invalid critical threshold: $opt_c\n");

+$SIG{'ALRM'} = sub { + print ("ERROR: timed out waiting for HylaFAX queue \n"); + exit $ERRORS{"WARNING"}; +}; +alarm($opt_t); +

my $sig=0;
my $ftp = Net::FTP->new($host, Port => $port);
if (not $ftp) {

@@ -67,6 +78,9 @@

$ftp->quit;
$sig = scalar(@jobs);

+## shut off the alarm +alarm(0); +

my $err = "OK";
if ($sig >= $critical) {
       $err = "CRITICAL";

@@ -91,6 +105,8 @@

       print "     connect to this port. Default is 4559.\n";
       print "  -l, --login=STRING\n";
       print "     connect using this login name.\n";

+ print " -t, --timeout=INTEGER\n"; + print " Plugin timeout in seconds (default = $utils::TIMEOUT)\n";

       print "  -p, --password=STRING\n";
       print "     connect using this password.\n";
       print "\n";