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

Hello and sorry for my english...
I'm trying to write a script from WinXP to connect to a linuxbox via SSH.
I'm using Net::SSH::Perl
My problem is that it responds:
Can't map service name 'ssh' to port number at script.pl line 11

Any suggestions please?

PS: Obviusly ssh is running in linuxbox on the default port... 
use Net::SSH::Perl;
use strict;
my $ssh = Net::SSH::Perl->new($host_ssh);
print "Sto per connettermi al server $host_ssh via ssh\n";
$ssh->login($user_ssh, $passwd_ssh);

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Replies are listed 'Best First'.
Re: connecting via SSH
by thor (Priest) on Mar 14, 2006 at 15:53 UTC
    In reading the docs for Net::SSH::Perl, it looks like it can take an optional port argument in the new method. Try: 
    use Net::SSH::Perl;
use strict;
my $ssh = Net::SSH::Perl->new($host_ssh, port => 22);
print "Sto per connettermi al server $host_ssh via ssh\n";
$ssh->login($user_ssh, $passwd_ssh);

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    and see if that does the trick. It'd be weird if that did it though; you'd think that that would be the default.

    thor

    The only easy day was yesterday

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      Normally, the default is accessed by getservbyname, but Windows doesn't have SSH in the "database" accessed by getservbyname. There are three solutions:

      • Specify the port explicitely, as suggested in the parent post.

      • Upgrade to version Net::SSH::Perl version 1.27 or higher. Instead of relying entirely on getservbyname, version 1.27 and higher use 22 (hardcoded) as the port number if getservbyname fails.

        Older version (<= 1.26): 

                my @serv = getservbyname(my $serv = $rport, 'tcp');
        $rport = $serv[2];
        croak "Can't map service name '$serv' to port number"
            unless defined $rport;

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        Newer version (>= 1.27): 

                my @serv = getservbyname(my $serv = $rport, 'tcp');
        $rport = $serv[2] || 22;

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      • Add SSH to the services "database". In windows, it's %SystemRoot%\system32\drivers\etc\services, a text file identical to unix's /etc/services. The entry to add is simply: 

        ssh 22/tcp  # Secure Shell Login

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      I'm really stuck.
      I've declared port as you suggested but when i start my script it responds:
      Your Vendor has not defined Fcntl macro F_SETFL, used at c:/Perl/site/lib/Net/SSH/Perl.pm line 218
      Which "Vendor" does it mean?? I can't understand the meaning...
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        That error means the OS doesn't support it that flag for fnctl, and that Perl doesn't emulate it. I don't know if that helps, but newer version of Net::SSH::Perl don't use F_SETFL.

        Older version (<= 1.26): 

            fcntl($sock, F_SETFL, O_NONBLOCK)
        or die "Can't set socket non-blocking: $!";

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        Newer version (>= 1.27): 

            defined($sock->blocking(0))
        or die "Can't set socket non-blocking: $!";

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        Check if you have the module Fcntl. I think it is installed with Perl by default. Btw, are you using Active State or Cygwin's Perl?

        Igor 'izut' Sutton
        your code, your rules.

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        fcntl is not very portable. That's why you get on an OS that support a particular fcntl flag and an fcntl that doesn't emulate it.

        ("Vendor" refers to the OS.)

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