ssh and perl

[umneydurak]

Hi.
I need to write a script that will connect to another server using SSH and execute some commands. The tricky part is that it has to provide a password, and it can't use any third party libraries. So no Net::SSH:erl. It gets better. Script will be run from multiple servers, but it will be connecting to one server. So creating a key pair for each server is just not an option. Is this possible to do? Please help.

Thank You.

 

[PaulTEG]

I'm not sure that what you ask is possible.
Why the objection to Net::SSH:erl? It's tried and tested and Open Source
--Paul

cigless ...

 

[umneydurak]

Because I have no control over the servers and what gets installed on them.

 

[PaulTEG]

You could make it a prerequisite for your software

cigless ...

 

[ishnid]

If you're able to install your own program on the server, then you have sufficient privileges to install Net::SSH:erl. It's a common misconception that you need root access to install Perl modules. You can install any module if you've even user-level shell access. If you're relying on FTP, it's a little trickier but pure-Perl modules such as Net::SSH:erl are still easily installed.

See here for more on this.

 

[Aradon]

If you don't use Net::SSH:erl then why not just use a shell script instead?

You could set up a public/private key system to bypass the tty password and then run the commands one at a time through the script.

I found the Net::SSH:erl to be useless in what I needed so I went for that route, cheers.

 

[umneydurak]

When I say I have no control over the server I really mean it. I can't install anything on it. Even if I found a way and did it the IT people would skin me alive. Also about the key thing. As I said it's not really an option. The script can be run from at least 20 servers. I don't even know what they all are. Asking a user to do it, isn't really an option either.
Anyway guess it can't be done. thanks.

 

[fishiface]

If what you have been asked to provide is a script that can be run from multiple servers, then can I assume that you are allowed to install the script on those servers and that they all have standard perl distributions installed?

If that is the case and, additionally, any non-standard modules that the script requires are pure perl modules, with a little work you can chain all the modules end to end in one script. You might need to enclose them in {} blocks and do a little extra work to preserve the effect of package globals and prevent scope problems but on the whole, splitting modules into separate files is a convenience, not a necessity.

This gives you a much more flexible basis from which to attack the problem.

f

"As soon as we started programming, we found to our surprise that it wasn't as easy to get programs right as we had thought. Debugging had to be discovered. I can remember the exact instant when I realized that a large part of my life from then on was going to be spent in finding mistakes in my own programs."
--Maurice Wilkes

 

[TrojanWarBlade]

Have you looked at "expect" and the perl expect module?



Trojan.

 

[PaulTEG]

You could be lucky and find the modules required are already installed

--Paul

cigless ...