There is a regression with dns handling between xenial and zesty. There are updates/improvements made in artful that will be published soon. It may not solve your issue, but maybe/hopefully it will improve things a lot.
systemd (234-1ubuntu2) artful; urgency=medium * Set UseDomains to true, by default, on Ubuntu. On Ubuntu, fallback DNS servers are disabled, therefore we do not leak queries to a preset 3rd party by default. In resolved, dnssec is also disabled by default, as too much of the internet is broken and using Ubuntu users to debug the internet is not very productive - most of the time the end-user cannot fix or know how to notify the site owners about the dnssec mistakes. Inherintally the DHCP acquired DNS servers are therefore trusted, and are free to spoof records. Not trusting DNS search domains, in such scenario, provides limited security or privacy benefits. From user point of view, this also appears to be a regression from previous Ubuntu releases which do trust DHCP acquired search domains by default. Therefore we are enabling UseDomains by default on Ubuntu. Users may override this setting in the .network files by specifying [DHCP|IPv6AcceptRA] UseDomains=no|route options. * resolved: create private stub resolve file for integration with resolvconf. The stub-resolve.conf file points at resolved stub resolver, but also lists the available search domains. This is required to correctly resolve domains without using resolve nss module. * Enable systemd-resolved by default * Create /etc/resolv.conf at postinst, pointing at the stub resolver. The stub resolver file is dynamically managed by systemd-resolved. It points at the stub resolver as the nameserver, however it also dynamically updates the search stanza, thus non-nss dns tools work correctly with unqualified names and correctly use the DHCP acquired search domains. * libnss-resolve: do not disable and stop systemd-resolved resolved is always used by default on ubuntu via stub resolver, therefore it should continue to operate without libnss-resolve module installed. -- Dimitri John Ledkov <x...@ubuntu.com> Fri, 21 Jul 2017 17:07:17 +0100 -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1699660 Title: systemd-resolve breaks resolution of local network hostnames Status in systemd package in Ubuntu: Confirmed Bug description: After upgrading to Ubuntu 17.04 (zesty), resolution of my local network's host names is completely broken. Apparently the upgrade replaced my existing resolver with systemd-resolve, which deliberately refuses to pass "single-label" domain names to my domain name server. That is the server where all my network's host names are kept, so I can no longer resolve any of them. Apparently, this is yet another example of Poettering's upstream decisions causing denial of service to people who have been saddled with his malware. https://github.com/systemd/systemd/issues/2514#issuecomment-179203186 Would someone sensible please put a stop to this forced breakage during upgrade, and advise on how to fix it now that the damage has been done? To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1699660/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp