Question

I’m working on a perl script using net::ssh2 to make a SSH connection to a remote server.
(I’m working on windows)

I chose Net::SSH2 because i had to make some SFTP connections in the same script.

For now, my sftp connections work perfectly. The problem is when i try to execute a “long-duration” command. I mean a command which execution can take more than 30sec.

    $ssh2 = Net::SSH2->new();
    $ssh2->connect('HOST') or die;
    if($ssh2->auth(username=>'USER', password=>'PSWD'))
    {
        $sftp = Net::SFTP::Foreign->new(ssh2=>$ssh2, backend=>'Net_SSH2');
        $sftp->put('local_path', 'remote_path');
        $channel=$ssh2->channel();
    ##
        $channel->shell('BCP_COMMAND_OR_OTHER_PERL_SCRIPT');
    # OR (I tried both, both failed :( )
        $channel->exec('BCP_COMMAND_OR_OTHER_PERL_SCRIPT');
    ##
        $channel->wait_closed();
        $channel->close();
        print "End of command";
        $sftp_disconnect();
    }
    $ssh2->disconnect();

When i execute this script, the connection is successfull, the file is correctly sent but the execution is not (completely) performed. I mean, I think the command is sent for execution but terminated immediatly or not sent at all, i’m not sure.

What i want is the script waits until the command is completly finished before disconnect everything (just because sometimes, i need to get the result of the command execution)

Does anyone know how to solve this? 🙁 The cpan documentation is not very explicit for this

Thanks!

PS: I’m open to any remarks or suggestion 🙂

Edit: After some test, i can say that the command is sent but is interrupted. My test was to start another perl script on the remote server. This script writes in a flat file. In this test, the script is started, the file is half-filled. I mean, the file is brutaly stopped in the middle.

In the other hand, when i performed a “sleep(10)” just after the “$channel->exec()”, the script goes to the end successfully.
Problem is, that I can’t write a “sleep(10)” (i don’t know if it will take 9 or 11 seconds (or more, you see my point)

Answer 1

You can try using Net::SSH::Any instead.

It provides a higher level and easier to use API and can use Net::SSH2 or Net::OpenSSH to handle the SSH connection.

For instance:

use Net::SSH::Any;

my $ssh = Net::SSH::Any->new($host, user => $user, password => $password);
$ssh->error and die $ssh->error;

my $sftp = $ssh->sftp;
$sftp->put('local_path', 'remote_path');

my $output = $ssh->capture($cmd);
print "command $cmd output:\n$output\n\n";

$sftp->put('local_path1', 'remote_path1');

# no need to explicitly disconnect, connections will be closed when
# both $sftp and $ssh go out of scope.

Note that SFTP support (via Net::SFTP::Foreign) has been added on version 0.03 that I have just uploaded to CPAN.