До сих пор пробегают глюки с DNSSEC, в браузере то одна, то другая страница не находятся... а потом опять находятся. Вот что пишет Поттеринг https://fedoraproject.org/wiki/Changes/systemd-resolved#DNSSEC systemd-resolved's DNSSEC support is known to cause compatibility problems with certain network access points (Reference #1, Reference #2). Per recommendation from the systemd developers, we will change the default value of this setting in Fedora from the upstream default DNSSEC=allow-downgrade to DNSSEC=no by building systemd with the build option -Ddefault-dnssec=no
*** This bug has been marked as a duplicate of bug 11597 ***