Dear monks,

I'm writing a small utility to monitor certain services on a dozen servers or so. I shouldn't have access on these servers, so I decided for the POP, SMTP and FTP monitoring to just check if their ports are open, since I wouldn't have access to check a logon.

I wrote this snippet:

sub checkports {
    
    my $sock;
    my ($pop, $smtp, $ftp) = @_;
    DEBUG && print "Checking ports : ";
    my %ports = (
            110 => $pop,
            25 => $smtp,
            21 => $ftp
        );
    
    for my $port (keys %ports) {
        DEBUG && print "[$port] ";
        
        $sock = new IO::Socket::INET(PeerAddr => $ports{$port}, PeerPo
+rt => $port, Proto => 'tcp', Timeout=>10);
        if ($sock) {
            $client->{"PORT$port"} = 'U';
            close $sock; 
        } else {
            $client->{"PORT$port"} = 'D';
        }
    }

    DEBUG && print " done.\n";
}

[download]

Since I have a fairly small knowledge in networking, I was wondering if this approach is reasonable; Is there another way to check if the services are up without having to get a username/password and try a real login?

He who asks will be a fool for five minutes, but he who doesn't ask will remain a fool for life.

Chady | http://chady.net/

In reply to Code Review: Checking open ports. by Chady

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