TedPride has asked for the wisdom of the Perl Monks concerning the following question:

SSH connections occasionally die randomly, and the computer I'm connecting to may also occasionally refuse connection. What I want is something that will allow me to continue whenever one of these errors occurs, rather than just dying and require a restart of the entire process.

To give you a small example, here is one function from my package, which is layered on top of Net::SFTP, which is in turn layered on top of Net::SSH::Perl:

sub openConnection { my $self = $_[0]; local $SIG{'__DIE__'} = sub {}; local $SIG{'__WARN__'} = sub {}; $self->{'sftp'} = Net::SFTP->new($::config{'ahost'}, user => $::config{'auser'}, password => $::config{'apass'}, ssh_args => [ options => [ 'ConnectTimeout 30', 'ServerAliveInterval 20', 'ServerAliveCountMax 3' ] ] ); if (!$self->{'sftp'}) { $self->{'error'} = "Unable to open SFTP connection"; return; } print "SFTP connection opened.\n"; return 1; }
This connects just fine when I use the correct credentials and the target server is running, but when I test it with a bad password or turn the target server off, I get a die from Net::SSH::Perl and that die does not get caught - even though I have $SIG{'__DIE__'} set. Wrapping the login inside eval { } causes scoping problems, and putting everything in a separate script and calling it via the command-line adds 30 seconds of overhead per transfer attempt, so those don't look like options either. What am I supposed to do?

I want to catch the die, detect that the connection attempt failed, and return false. Or turn off die somehow.