At https://docs.freebsd.org/en_US.ISO8859-1/books/porters-handbook/port-upgrading.html appears this text in the second paragraph: When working with more than a few ports, it will probably be easier to use Subversion to keep the whole ports collection up-to-date, as described in the Handbook. "Handbook" links to https://docs.freebsd.org/doc/en_US.ISO8859-1/books/handbook/ports-using.html which is a 404
The issue is https://docs.freebsd.org/en_US.ISO8859-1/books/porters-handbook/port-upgrading.html is legacy page and the latest one should be https://docs.freebsd.org/en/books/porters-handbook/upgrading/ So the issue we need to fix is the SEO (the legacy URLs shouldn't be indexed by search engines and we should provide a better redirection to the latest pages.
Is there any reason that the legacy content can't just be deleted? It seems that deploying into a clean docroot would be a good start.
There are redirects in place for almost all legacy links now. $ curl -sLI https://docs.freebsd.org/en_US.ISO8859-1/books/porters-handbook/port-upgrading.html | egrep 'HTTP|Location' HTTP/1.1 302 Moved Temporarily Location: https://docs.freebsd.org/en/books/porters-handbook/upgrading/ HTTP/1.1 200 OK Thanks for reporting it.
Fix confirmed here. Thank you.