Broken DNS when using Three UK mobile internet (17.04 zesty)

[Reupen Shah]

When connected via 4G to Three/3 (UK), DNS lookups fail (though the internet is otherwise working).

The connection receives the correct DNS servers, but as far as I can work out systemd-resolve is unaware of them.

Connection info screenshot is attached.

DNS lookups time out:

$ nslookup www.bbc.co.uk
;; connection timed out; no servers could be reached

However they work when manually specifying the DNS server:

$ nslookup www.bbc.co.uk 217.171.132.0
Server: 217.171.132.0
Address: 217.171.132.0#53

Non-authoritative answer:
www.bbc.co.uk canonical name = www.bbc.net.uk.
Name: www.bbc.net.uk
Address: 212.58.246.54
Name: www.bbc.net.uk
Address: 212.58.244.26

Connections to IP addresses work (though redirect to a Three page at present):

$ curl http://212.58.246.54 -v
* Rebuilt URL to: http://212.58.246.54/
* Trying 212.58.246.54...
* TCP_NODELAY set
* Connected to 212.58.246.54 (212.58.246.54) port 80 (#0)
> GET / HTTP/1.1
> Host: 212.58.246.54
> User-Agent: curl/7.52.1
> Accept: */*
>
< HTTP/1.1 302 Moved Temporarily
< Location: http://mbbinfo.three.co.uk/payg_mbb_data_usage2.html
< Content-Type: text/plain; charset=UTF-8
< Content-Length: 0
<
* Curl_http_done: called premature == 0
* Connection #0 to host 212.58.246.54 left intact

Below is the output of systemd-resolve --status:

$ systemd-resolve --status
Global
         DNS Servers: 8.8.8.8
                      8.8.4.4
                      2001:4860:4860::8888
                      2001:4860:4860::8844
          DNSSEC NTA: 10.in-addr.arpa
                      16.172.in-addr.arpa
                      168.192.in-addr.arpa
                      17.172.in-addr.arpa
                      18.172.in-addr.arpa
                      19.172.in-addr.arpa
                      20.172.in-addr.arpa
                      21.172.in-addr.arpa
                      22.172.in-addr.arpa
                      23.172.in-addr.arpa
                      24.172.in-addr.arpa
                      25.172.in-addr.arpa
                      26.172.in-addr.arpa
                      27.172.in-addr.arpa
                      28.172.in-addr.arpa
                      29.172.in-addr.arpa
                      30.172.in-addr.arpa
                      31.172.in-addr.arpa
                      corp
                      d.f.ip6.arpa
                      home
                      internal
                      intranet
                      lan
                      local
                      private
                      test

Link 4 (wlp4s0)
      Current Scopes: none
       LLMNR setting: yes
MulticastDNS setting: no
      DNSSEC setting: allow-downgrade
    DNSSEC supported: yes

Link 3 (wwp0s20f0u6i12)
      Current Scopes: LLMNR/IPv4 LLMNR/IPv6
       LLMNR setting: yes
MulticastDNS setting: no
      DNSSEC setting: allow-downgrade
    DNSSEC supported: yes

Link 2 (enp0s31f6)
      Current Scopes: none
       LLMNR setting: yes
MulticastDNS setting: no
      DNSSEC setting: allow-downgrade
    DNSSEC supported: yes

Note: Everything works fine on Wi-Fi, this problem is only happening on 4G.

Note 2: I removed the automatically added UdevDb.txt and CurrentDmesg.txt attachments as they contained serial numbers of devices in my computer (such as for my SSD).

ProblemType: Bug
DistroRelease: Ubuntu 17.04
Package: systemd 232-21ubuntu2
ProcVersionSignature: Ubuntu 4.10.0-19.21-generic 4.10.8
Uname: Linux 4.10.0-19-generic x86_64
ApportVersion: 2.20.4-0ubuntu4
Architecture: amd64
CurrentDesktop: Unity:Unity7
Date: Sat Apr 15 20:54:33 2017
InstallationDate: Installed on 2017-04-08 (7 days ago)
InstallationMedia: Ubuntu 17.04 "Zesty Zapus" - Beta amd64 (20170407)
MachineType: LENOVO 20HDCTO1WW
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.10.0-19-generic.efi.signed root=UUID=88cb6912-997a-41b4-a0f8-050239177218 ro quiet splash vt.handoff=7
SourcePackage: systemd
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 03/29/2017
dmi.bios.vendor: LENOVO
dmi.bios.version: N1QET53W (1.28 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20HDCTO1WW
dmi.board.vendor: LENOVO
dmi.board.version: SDK0J40697 WIN
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.modalias: dmi:bvnLENOVO:bvrN1QET53W(1.28):bd03/29/2017:svnLENOVO:pn20HDCTO1WW:pvrThinkPadT470:rvnLENOVO:rn20HDCTO1WW:rvrSDK0J40697WIN:cvnLENOVO:ct10:cvrNone:
dmi.product.name: 20HDCTO1WW
dmi.product.version: ThinkPad T470
dmi.sys.vendor: LENOVO

[Reupen Shah (reupen)]

Update: The ISP redirect has now gone away and the internet now works. However, if the output of systemd-resolve --status is anything to go by systemd-resolve appears to still be using Google DNS instead of my ISP's (which seems utterly bizarre).

I would surmise that while the redirect was in place, systemd-resolve was using Google DNS and access to the Google DNS servers was blocked until the SIM had been set up. This basically makes it impossible to set up the type of SIM I had (https://www.three.co.uk/Free_SIM_MBB/Order) on Ubuntu (I had to do that on Windows). That's because the SIM requires registration, which you have to do via mobile internet while using the SIM.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[DieterDrewanz (dieterd2005)]

Similar trouble I have on connections with
systemd-resolve --status
DNSSEC supported: yes

Working with no trouble are connections with
DNSSEC supported: no

Using an old android smartphone or an old|really stupid wlan-router lacks this support and therefore dns resolving is not disturbed. Yeah these idea l will need to install bug-fix in future when available (will solve hen-egg problem).

[DieterDrewanz (dieterd2005)]

From here I picked idea of testing different wlan connections (router and smart phone as hot spot) and looking for differences. Although there was another reason for this bug and this bug is not similar but some similar error messages.

[Steve Langasek (vorlon)]

Thank you for reporting this problem and helping to improve Ubuntu.

When you were connecting to this 4G network, how was that connection managed? Were you using NetworkManager, or some other network management tool?

[Reupen Shah (reupen)]

Presumably NetworkManager, I just selected 3 Internet from the connections icon in the top-right corner of the screen (after disabling Wi-Fi from the same place).

However, I'm now running Ubuntu 17.10 and systemd-resolve --status is showing the correct DNS servers when connected to 4G. So, this appears to now be fixed, and this report can be closed.