connect to localhost failed (Connection refused) no (more) retries - perl

Question

I want to send an email using perl ,but when i execute the command as follows:
#./sendmail.sh "par1" "par2" "par3"
i got the error msg "connect to localhost failed (Connection refused) no (more) retries"
sendmail.sh:
/usr/bin/perl /code/sendmail.pl "$1" "$2" "$3";
sendmail.pl:
#!/usr/bin/perl -w
use Mail::Sendmail;
my $event1 = shift(#ARGV);
my $event2 = shift(#ARGV);
my $time = shift(#ARGV);
#my $info = shift(#ARGV);
my $datetime = `/bin/date "+20%y-%m-%d %H:%M:%S"`;
chomp $datetime;
$msg = "This is Monitor System speak:\n
The system discovers the events at $datetime.
Something may be abnormal, please check it. The detail is below:\n";
$msg = $msg."$event1 and $event2 at $time\n";
$msg = $msg."\n";
$msg = $msg."Any problem, check it from http://map_test.php\n\n\n";
$mail_subject = "Abnormal";
sendmail(
From => 'localhost',
To => 'test#mail.com',
Subject => $mail_subject,
Message => $msg,
);
Any help appreciated.

Answer 1

smtp stands for simple mail transfer protocol.
When you need to send an email your mail client needs to talk to an smtp server which will accept the message. Normally your internet service provider will provide an smtp host. If you look at your mail client it will need to have an smtp server configured to be able to send mail.
Ok so when you install the Mail::Sendmail module, it doesn't know what your smtp server will be. It is up to you to tell it. It provides a default of localhost which would often be true if your server is running a sendmail daemon.
The configuration of Mail::Sendmail is stored in a variable called
%Mail::Sendmail::mailcfg
You can change the value of the sendmail server using this snippet of code:
unshift #{$Mail::Sendmail::mailcfg{'smtp'}} , 'my.smtp.server';
You need to add this line of code to your script to set the smtp server.
It adds this server to an array which also includes localhost.
So if neither of the hosts work it will still print an error message about localhost which is slightly confusing.
If you use Data::Dumper to print the contents of the mailcfg variable it will look something like this:
#!/usr/bin/perl
use Mail::Sendmail;
use Data::Dumper;
unshift #{$Mail::Sendmail::mailcfg{'smtp'}} , 'my.smtp.server';
print Dumper(\%Mail::Sendmail::mailcfg);
Should return:
$VAR1 = {
'retries' => 1,
'smtp' => [
'my.smtp.server',
'localhost'
],
'delay' => 1,
'port' => 25,
'from' => '',
'debug' => 0,
'tz' => '',
'mime' => 1
};