How to monitor linux machine

Hello

I have a nagios installed on my machine and im using ubuntu linux
i used nsclient for my windows client and everythings works fine
my question is how can i monitor my other linux machine not unlike in windows i just to install the nsclient and config and it works fine
but in linux what software or plugins do i need to install it or do i need to install nagios in my other linux machine? just like im doing on my nagios server.

please help

thanks

check_by_ssh or use NRPE (or was it NSCA?) to execute checks on the remote server and pass the data to your active nagios install.

check_by_ssh only needs the plugins on the remote server… have a look at both solutions and choose the one which fits best to your needs.