perlbrew usually picks some nice defaults, but you can still tweaks some knobs.
Set environment variable PERLBREW_CPAN_MIRROR to the mirror site url. http://` orhttps://` URLs
are both supported, but not ftp:// or rsync:// URLs.
For example:
# bash / zsh
export PERLBREW_CPAN_MIRROR=https://cpan.metacpan.org/
For the list of public CPAN mirror site URLs, please see this list Again, choose a `http://` URL.