in reply to PAR::Packer link to lower glibc version
I also have to manage Perl scripts that get run on a variety of servers with various OS's (but they're all unix). I copy the actual perl script to each server. For CPAN modules, I use the "install local" option on one server, then I tar up that lib directory, and copy it to the others. Set the PERL5LIB env var to the path of this lib so that perl can find it. For modules that have binary parts and/or require compiling etc., I'd recommend building on the oldest OS, and copying out from there.
I would only use PAR::Packer if I needed to deploy to a Windose box for some reason. Don't install modules as root, since you might accidentally break your system perl (or change the behavior of scripts used by the OS). If I need to change something, I test on one machine, then push out the new version to the other s using rsync.