The problem is on cpan version is out of date, it’s still trying to detect file search.cpan.org which doesn't exist.
This case you'll need to update cpan in your server by this guide:
Edit file
/root/.cpan/CPAN/MyConfig.pm
Or
/usr/share/perl5/CPAN/Config.pm
Change urllist
to be
'urllist' => [
q[http://httpupdate3.cpanel.net/CPAN/],
q[http://httpupdate23.cpanel.net/CPAN/],
q[http://mirrors.servercentral.net/CPAN/],
q[ftp://cpan.cse.msu.edu/]
],
After that, install RVsitebuilder again.