I am trying to add a check for the smtp server not being available. Here is the code (without the error check):

my $mailer = new Mail::Mailer('smtp', Server =>  $mailserver);

my %headers=();

$headers{'To'} = "$recipient_email";
$headers{'From'} = "$sender_email";
$headers{'Subject'} = "$subject_email";

$mailer->open(\%headers);
[download]

If the $mailserver is not found or the smtp service is not available, then the last line fails with either "No such host is known." or "The requested name is valid and was found in the database, but it does not have the correct associated data being resolved for."

I have tried:
$mailer->open(\%headers) || die ("cannot find smtp server");
with the same results.

I have also tried various if statements, but am not sure for what condition to check.

Any suggestions? Thanks!!