Please consider reading "How (Not) To Ask A Question" before your next post. Especially the part about formatting. I'm having a real tough time reading your post.

I'm at a loss for understanding what you mean by "virtual router" in your post. Is this some entity that exists only in software? Secondly, the "system" function may not be what you need to make things happen. Normally (and I've done this quite a bit) a router or other network element has a management interface of some sort either via console or some type of web interface.

In the case of a serial console I'd recommend reading up on the CPAN modules Net::Telnet and/or Net::Telnet::Cisco. These modules do an excellent job of allowing one to programatically manipulate a router.

In the case of a web interface I would look at LWP::UserAgent or WWW::Mechanize but I'll warn you that will be a bit more complicated.

All system() does is send things to the command line from whatever shell you invoked the Perl script from. Unless you are running the Perl code on your router, which would surprise me, this isn't going to have the affect you're after.