[Ssh-sftp-perl-users] Problem getting output using Net::SSH2

[Steve P. <st...@fo...>]

Hey There,

I'm busy pulling my hair out over this one. I have a small script 
similar to the below.

my $ssh2 = Net::SSH2->new();
$ssh2->debug(1);
$ssh2->connect($server) or die "Unable to connect Host $@ \n";
$ssh2->auth_publickey($userName,$publicKey,$privateKey);

my $chan = $ssh2->channel();
$chan->blocking(0);
$chan->shell();

This seems to work quite happily and a connection is established, 
however - when running small commands (ls -l, whoami etc) everything 
works as expected

print $chan "ls -la\n";
while (<$chan>) { print "LINE: " . $_ }

But, when I run a command that takes a while to return, I simply get a 
blank output.

print $chan "vip/listmse /WideSpan/config/vipclient.conf 1 -c 'RADIUS 
Server'\n";
while (<$chan>) { print "LINE: " . $_ }

The only thing I can think of is that the second command seems to take a 
few miliseconds longer to produce output.

I've tried to play around with "$ssh2->poll(0)" which I read somewhere 
sets polling to infinite, but still no results.

When debug is enabled I get thousands of lines similar to

Net::SSH2::Channel::read(size = 1, ext = 0)
- read 1 bytes
- read 1 total
Net::SSH2::poll: timeout = 250, array[1]
- [0] = channel
- [0] events 1
- libssh2_poll returned 1
- [0] revents 1

scrolling up the screen, which I would assume means that I have exceeded 
a timeout of 250ms ?

I've tried setting blocking to 0 and 1 with no joy either. (I've found 
that setting blocking to 0 when performing shell commands can lead to 
interesting output tho, so I assume that interactive shell commands 
should leave blocking to 1 ? setting to 0 seems to have interesting 
results when trying to run commands like ls -la)

If I manually ssh into the remote box and run the command it returns 
values as expected, and if I do something similar using Net::SSH::Perl 
it works as well, however, Net::SSH::Perl seems to take upward of 30 
seconds to create a connection which isn't an option in this environment 
(and yeah - I've tried all the math module stuff which didn't seem to 
make a difference :-( )

Any pointers as to why small/fast commands would work but commands that 
take around 1/2 a second to run would drop out would be appreciated.

-- 
Steve.