hi This may help you.. 
If you want to generate keys using SSH for automatic login / passwordl
+ess login then follow the steps

A -> your server where from you want to login remote servers
B, C servers you want to monitor
---------
- login to A
- ssh-keygen -t rsa
ENTER - ENTER - ENTER 
- chmod 600 $HOME/.ssh/id_rsa
- cat $HOME/.ssh/id_rsa.pub
- copy this into 1 line into $HOME/.ssh/authorized_keys file of server
+ B and C.

It can be first time you have to login each server manually, but since
+ 2nd try it login automatically.

=> you can copy the id_rsa.pub too with scp like this:
cd .ssh/
scp id_rsa.pub username@12.18.1.3:./authorized_keys

[download]
this is how the passwordless logins are made.if you want to run multiple commands do use '|' symbol and regarding the Net::SSH is also a best option to access the devices remotely and it is secure than telnet. i have done a project using NET::TELNET::CISCO to login into network devices and check for certain parameters.

In reply to Re^2: Installing Net::SSH::Perl on OS X, or how to run commands remotely by pingme8705
in thread Installing Net::SSH::Perl on OS X, or how to run commands remotely by kazeeks

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