Problem With Net::SSH::Expect using Multi threads

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

Hi Monks,

I was trying a code for executing commands on remote system using Net::SSH:Expect module. I have no problem in working with the code without multithreading. But when I appended threads with the existing code for better performance, it was giving errors.

Here is the code:


#!/usr/bin/perl
use Net::SSH::Expect;
use threads;

@hosts = ('192.168.1.222',192.168.1.169);

my $machine;

foreach $machine ( @hosts )
{

        push @threads, threads->create(\&sshd,$machine);
}

 while ( my $thread = shift @threads ) {
                $thread->join ;
              print " Thread [ $machine ] Ending ... \n";
          }

sub sshd
{
        my $ssh = Net::SSH::Expect->new(host=>'$ip', user=>'root',pass
+word=>'access') or die "cannot open";

          $login_check=$ssh->login();
        print "LOGIN for $ip -- $login_check \n";

        my $who = $ssh->exec('hostname');

        my $ls = $ssh->exec('ls -l |grep Desktop');
        print "$who \n";
        print "$ls \n";
        $ssh->close();
}
[download]

Error:

ssh: : Name or service not known

thread failed to start: SSHConnectionAborted at sshnew.pl line 30

Thread Ending ...

please tell me any possible solution

Thanks in Advance.

Comment on Problem With Net::SSH::Expect using Multi threads Download Code

Replies are listed 'Best First'.
Re: Problem With Net::SSH::Expect using Multi threads by Joost (Canon) on Aug 20, 2007 at 13:32 UTC
Since you're not sharing any information, using fork should work just as well as threads without the headaches, and will probably perform better. Unless you're on Win32. "What should it profit a man, if he should win a flame war, yet lose his cool?"	[reply]
Re^2: Problem With Net::SSH::Expect using Multi threads by Anonymous Monk on Aug 20, 2007 at 13:42 UTC
Hey I am compeled to use threads. Any other solution?	[reply]
Re^3: Problem With Net::SSH::Expect using Multi threads by Joost (Canon) on Aug 20, 2007 at 14:04 UTC
According to http://search.cpan.org/~rgiersig/Expect-1.21/Expect.pod#Is_it_possible_to_use_threads_with_Expect? you should construct each Expect object in the main thread and then spawn the subthread to handle it. I've no idea if that will actually work, but it's worth a try. In general, it's not a great idea to force perl threads on a problem unless you either know that it'll work, or you've got a very good reason to prefer threads over fork() AND you've got the time to fix various bugs like this (and worse). "What should it profit a man, if he should win a flame war, yet lose his cool?"	[reply]
Re: Problem With Net::SSH::Expect using Multi threads by Anonymous Monk on Aug 20, 2007 at 13:02 UTC
try #!/usr/bin/perl use threads; @hosts = ('192.168.1.222',192.168.1.169); my $machine; foreach $machine ( @hosts ) { push @threads, threads->create(\&sshd,$machine); } while ( my $thread = shift @threads ) { $thread->join ; print " Thread [ $machine ] Ending ... \n"; } sub sshd { require Net::SSH::Expect; my $ssh = Net::SSH::Expect->new(host=>'$ip', user=>'root',pass +word=>'access') or die "cannot open"; $login_check=$ssh->login(); print "LOGIN for $ip -- $login_check \n"; my $who = $ssh->exec('hostname'); my $ls = $ssh->exec('ls -l \|grep Desktop'); print "$who \n"; print "$ls \n"; $ssh->close(); } [download]	[reply] [d/l]
Re^2: Problem With Net::SSH::Expect using Multi threads by Anonymous Monk on Aug 20, 2007 at 13:25 UTC
We have tried with replacing `require Net::SSH::Expect;` [download] in the sub-routine but no luck	[reply] [d/l]