[Bug 1727237] Re: systemd-resolved is not finding a domain

[Pete]

I also have been experiencing this. Connecting to WiFi network that uses
any captive portal fails.

I dual boot with Windows, and everything is fine in Windows.

System: 
Ubuntu 17.10 (Clean install)

Behavior:
After authenticating with the portal and connecting I cannot resolve DNS.

My work around (after a lot of digging) was to edit "/etc/resolv.conf"

And add "nameserver 8.8.8.8" (Google Public DNS)

So my nameserver looked liked:

nameserver 127.0.0.53
nameserver 8.8.8.8

I had to do this after every reboot obviously.

Also very peculiar:
I have been using this work-around every day since installing 17.10 one week ago. However, I connected to a regular home WiFi network (non-captive portal) fine last night. Then after returning to my work captive-portal WiFi network its now connecting and resolving DNS successfully. Without having to update my /etc/resolv.cong. I don't understand why...

Wanted to mention while searching forums and bug reports I came across
many reported bugs that are likely duplicates of this issue. Where users
are reporting spotty or intermittent WiFi issues etc. Many think its
kernel and driver issues, while this isn't the case.

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to systemd in Ubuntu.
https://bugs.launchpad.net/bugs/1727237

Title:
  systemd-resolved is not finding a domain

Status in systemd package in Ubuntu:
  Triaged
Status in systemd source package in Xenial:
  Triaged
Status in systemd source package in Zesty:
  Won't Fix
Status in systemd source package in Artful:
  Triaged
Status in systemd source package in Bionic:
  Triaged

Bug description:
  I have an odd network situation that I have so far managed to narrow
  down to the inability to resolve a domain via systemd-resolved which
  is resolvable with nslookup. If I use nslookup against the two
  nameservers on this network I get answers for the domain, but ping
  says it is unable to resolve the same domain (as do browsers and
  crucially the captive portal mechanism).

  Here are details:

  NSLOOKUP:

  ~$ nslookup securelogin.arubanetworks.com 208.67.220.220
  Server:		208.67.220.220
  Address:	208.67.220.220#53

  Non-authoritative answer:
  Name:	securelogin.arubanetworks.com
  Address: 172.22.240.242

  ~$ nslookup securelogin.arubanetworks.com 208.67.222.222
  Server:		208.67.222.222
  Address:	208.67.222.222#53

  Non-authoritative answer:
  Name:	securelogin.arubanetworks.com
  Address: 172.22.240.242

  
  PING:

  ~$ ping securelogin.arubanetworks.com
  ping: securelogin.arubanetworks.com: Name or service not known
  mark at mark-X1Y2:~$ 

  
  DIG:

  ~$ dig @208.67.222.222 securelogin.arubanetworks.com

  ; <<>> DiG 9.10.3-P4-Ubuntu <<>> @208.67.222.222 securelogin.arubanetworks.com
  ; (1 server found)
  ;; global options: +cmd
  ;; Got answer:
  ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 9416
  ;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

  ;; OPT PSEUDOSECTION:
  ; EDNS: version: 0, flags:; udp: 4096
  ;; QUESTION SECTION:
  ;securelogin.arubanetworks.com.	IN	A

  ;; AUTHORITY SECTION:
  arubanetworks.com.	1991	IN	SOA	dns5.arubanetworks.com. hostmaster.arubanetworks.com. 1323935888 3600 200 1209600 86400

  ;; Query time: 34 msec
  ;; SERVER: 208.67.222.222#53(208.67.222.222)
  ;; WHEN: Wed Oct 25 10:31:10 CEST 2017
  ;; MSG SIZE  rcvd: 144

  
  MORE DIG:

  ~$ dig securelogin.arubanetworks.com

  ; <<>> DiG 9.10.3-P4-Ubuntu <<>> securelogin.arubanetworks.com
  ;; global options: +cmd
  ;; Got answer:
  ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 3924
  ;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

  ;; OPT PSEUDOSECTION:
  ; EDNS: version: 0, flags:; udp: 65494
  ;; QUESTION SECTION:
  ;securelogin.arubanetworks.com.	IN	A

  ;; Query time: 0 msec
  ;; SERVER: 127.0.0.53#53(127.0.0.53)
  ;; WHEN: Wed Oct 25 10:34:01 CEST 2017
  ;; MSG SIZE  rcvd: 58

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1727237/+subscriptions