Yesterday Lars Ingebrigtsen, who established and has run Gmane since 2002, posted an article saying that Gmane might go away [1].
He posted an update [2] which says the Gmane archive *has* gone away and unless someone steps up to take it over, it is gone for good. The OpenVPN mailing list archives are still available on SourceForge, but it might be worth thinking about adding openvpn-dev and openvpn-users to The Mail Archive [3] or some other such service. [1] https://lars.ingebrigtsen.no/2016/07/28/the-end-of-gmane [2] https://lars.ingebrigtsen.no/2016/07/28/the-end-of-gmane/comment-page-1/#comment-13502 [3] https://www.mail-archive.com