As for ubuntu.com, that was only as an example to show a situations when things break. I really just copied what the original submitter used -- I should probably have used example.com instead though, that's less confusing.
My concrete situation is that the server delivers only inf.uni- konstanz.de because that's what matches the university's organizational structure. (And having it changed it is not an option.) I put the other two (disy.inf.uni-konstanz.de and uni-konstanz.de) in the search path long ago because I regularly connect to hosts in those domains. Saves a lot of typing errors, and AFAIK it's not an uncommon use case for the search path. But this broke DNS resolution for disy.inf.uni-konstanz.de and uni-konstanz.de (probably because they're not in any per-interface search path) on upgrade to 17.04, and got me to this bug. As far as I can tell now, the bug should only affect users on or upgrading to zesty who have manually configured a search path using resolvconf, and artful users who configure one in resolved.conf. That's clearly a minority of users. I certainly agree to the "only send queries to the right nameserver" part. That makes sense, as does UseDomains and setting it to true by default. What I find troubling is that it seems to just swallow the query when there's no interface matching a search path entry. That doesn't agree with the documentation of either Domains= or UseDomains=, which both suggest that one can have search paths not associated with an interface. But I guess that's a bug in the systemd-resolved and not in Ubuntu, so I'll probably just report it upstream. -- 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/1714803 Title: Search list in resolv.conf breaks resolving for that domain Status in systemd package in Ubuntu: Incomplete Bug description: Ubuntu 17.04 systemd 232-21ubuntu5 Adding a domain to the search list in /etc/resolv.conf breaks resolving for that domain. Not only does the search list not get used as expected, but host names in the domain cannot be resolved by systemd-resolved at all. I just ran into this after upgrading from ubuntu 16.04 to 17.04 which enabled systemd-resolved. I have for a long time used resolveconf to add a 'search my-domain'-line to my /etc/resolv.conf. Example of expected behaviour. With Googles DNS server (8.8.8.8) and ubuntu.com in the search list in /etc/resolv.conf. Both dig and systemd-resolve can resolve www.ubuntu.com and www: $ cat /etc/resolv.conf nameserver 8.8.8.8 search ubuntu.com $ dig +nostat +nocmd www.ubuntu.com ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 55037 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 512 ;; QUESTION SECTION: ;www.ubuntu.com. IN A ;; ANSWER SECTION: www.ubuntu.com. 501 IN A 91.189.89.115 $ dig +search +nostat +nocmd www ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 25772 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 512 ;; QUESTION SECTION: ;www.ubuntu.com. IN A ;; ANSWER SECTION: www.ubuntu.com. 382 IN A 91.189.89.103 $ systemd-resolve www.ubuntu.com www.ubuntu.com: 91.189.89.115 -- Information acquired via protocol DNS in 2.7ms. -- Data is authenticated: no $ systemd-resolve www www: 91.189.90.59 (www.ubuntu.com) -- Information acquired via protocol DNS in 3.8ms. -- Data is authenticated: no Ubuntu 17.04 default config, with the systemd-resolved name server in /etc/resolv.conf and no search list. www.ubuntu.com can still be resolved correctly: $ cat /etc/resolv.conf nameserver 127.0.0.53 $ dig +nostat +nocmd www.ubuntu.com ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 64646 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 65494 ;; QUESTION SECTION: ;www.ubuntu.com. IN A ;; ANSWER SECTION: www.ubuntu.com. 482 IN A 91.189.89.110 $ systemd-resolve www.ubuntu.com www.ubuntu.com: 91.189.90.58 -- Information acquired via protocol DNS in 18.2ms. -- Data is authenticated: no Broken behaviour, using the systemd-resolved name server and specify ubuntu.com in search list. Resolving fails for www.ubuntu.com and www, both using dig (DNS) and using sytemd-resolve: $ cat /etc/resolv.conf nameserver 127.0.0.53 search ubuntu.com $ dig +nostat +nocmd www.ubuntu.com ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 33334 ;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 65494 ;; QUESTION SECTION: ;www.ubuntu.com. IN A $ dig +search +nostat +nocmd www ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 50588 ;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 65494 ;; QUESTION SECTION: ;www.ubuntu.com. IN A $ systemd-resolve www.ubuntu.com www.ubuntu.com: resolve call failed: No appropriate name servers or networks for name found $ systemd-resolve www www: resolve call failed: All attempts to contact name servers or networks failed To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1714803/+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