CPAN Proxy Settings Depend on the Actual Downloader

If CPAN accepts its proxy setting but downloads by another route, read the diagnostic output for the selected downloader. CPAN.pm can use Perl networking modules or delegate to an external program.

Inspect the current interactive configuration:

cpan> o conf http_proxy
cpan> o conf ftp_proxy
cpan> o conf no_proxy
cpan> o conf urllist

urllist selects the destination mirror and scheme, not the intermediary. An HTTP proxy fetching an FTP resource remains an HTTP listener; the field name does not turn it into an FTP server.

If the transfer invokes curl, inspect that child's inherited environment. A scoped launch is:

http_proxy=http://proxy.example:8080 https_proxy=http://proxy.example:8080 cpan

For public mirror downloads on a network allowing that route, replace the example with a no-account candidate from the HTTP proxy list. This supplies the HTTP endpoint to CPAN and its children unless another launcher changes the environment. Curl reads lowercase http_proxy; the HTTPS destination setting may name the same HTTP listener.

If CPAN selects LWP, follow its configured values and client behavior instead. Curl being installed does not prove CPAN used it. Avoid installing modules or editing startup files before identifying that selection.

Persist intended CPAN changes with o conf commit under the account performing installation, and keep secrets out of shared examples. This is the interactive CPAN.pm client; cpanm can choose another downloader and configuration even with the same mirror.