<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">Hello.<div class=""><br class=""></div><div class="">I have a Nginx server which acts as a reverse proxy for a given number of different domains and I’m trying to enable http3 for a subset of them.</div><div class=""><br class=""></div><div class="">I placed the directives:</div><div class=""><br class=""></div><div class=""><blockquote type="cite" class=""><div class=""> http3 on;</div><div class=""> listen xx.xx.xx.xx:443 default_server quic reuseport;</div><div class=""> quic_retry on;</div></blockquote><br class=""></div><div class="">in the default.conf file and then, only for those domains which I want http3 enabled I also add in the corresponding virtual host:</div><div class=""><br class=""></div><div class=""><blockquote type="cite" class=""><div class=""> http3 on;</div><div class=""> listen xx.xx.xx.xx:443 quic;</div><div class=""> quic_retry on;</div></blockquote><div class=""><br class=""></div>In the server section and <br class=""><br class=""></div><div class=""><blockquote type="cite" class=""><pre style="padding: 0px; margin-top: 0px; margin-bottom: 0px; font-variant-ligatures: normal; orphans: 2; widows: 2; background-color: rgb(255, 255, 255); text-decoration-thickness: initial;" class="">add_header Alt-Svc 'h3=":8443"; ma=86400';</pre></blockquote><div class=""><br class=""></div></div><div class="">Inside the location.</div><div class=""><br class=""></div><div class="">Now, what happens is that if I try to open the sites *with* http3 enabled, everything works as expected. If I try to open a site *without* http3 enabled, sometimes I have an SSL error because the server returns the “default virtual host” certificate.</div><div class="">It seems related to the type of browser.</div><div class=""><br class=""></div><div class="">Is it an expected behaviour or I am doing something wrong with the server configuration?</div><div class=""><br class=""></div><div class="">Nginx version: nginx/1.26.1 on ubuntu 22.04</div><div class=""><br class=""></div><div class="">Thanks.</div><div class="">Riccardo</div></body></html>