DNS doesn't work

[Jon Watte]

I am running a fresh install of Ubuntu Desktop 17.10 on a Dell XPS 15 9560 laptop.
I'm using an external Thunderbolt dock to connect to wired Ethernet.
I have additionally installed openssh-server on the system.

When I boot the system as normal, NetworkManager ends up creating a resolv.conf file that contains "nameserver 127.0.1.1"
However, with this file, DNS doesn't work -- "ping www.google.com" doesn't resolve, web pages don't resolve, ubuntu update doesn't find servers, and so forth.

If I do the following, the system works fine:
"mv /etc/resolv.conf /etc/resolv.conf.old"
"echo 'nameserver 8.8.8.8' > /etc/resolv.conf"
But I have to re-do this every time I boot.

I have configured manual DNS as 8.8.8.8,8.8.4.4 in the properties for the Wired network connection.
It also doesn't work if I use the default DHCP servers (Comcast, who poisons DNS for their customers so I generally don't use that.)

My DHCP server is a MikroTik Routerboard Router/Access point (I'm using wired Ethernet for now.)
Other wired machines on the same network work fine, including older versions of Ubuntu with DNS set to 8.8.8.8.

netstat -naplt udp doesn't show anything listening on port 53 locally, I don't know of that's expected or not for whatever the 127.0.1.1 proxy is.

ProblemType: Bug
DistroRelease: Ubuntu 17.10
Package: network-manager 1.8.4-1ubuntu3
ProcVersionSignature: Ubuntu 4.13.0-32.35-generic 4.13.13
Uname: Linux 4.13.0-32-generic x86_64
ApportVersion: 2.20.7-0ubuntu3.7
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Fri Feb 9 10:53:31 2018
IfupdownConfig:
 # interfaces(5) file used by ifup(8) and ifdown(8)
 auto lo
 iface lo inet loopback
InstallationDate: Installed on 2018-02-09 (0 days ago)
InstallationMedia: Ubuntu 17.10 "Artful Aardvark" - Release amd64 (20180105.1)
IpRoute:
 default via 10.0.0.1 dev enxa44cc88a6c8b proto static metric 100
 10.0.0.0/8 dev enxa44cc88a6c8b proto kernel scope link src 10.0.0.40 metric 100
 169.254.0.0/16 dev enxa44cc88a6c8b scope link metric 1000
NetworkManager.state:
 [main]
 NetworkingEnabled=true
 WirelessEnabled=true
 WWANEnabled=true
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: network-manager
UpgradeStatus: No upgrade log present (probably fresh install)
nmcli-con:
 NAME UUID TYPE TIMESTAMP TIMESTAMP-REAL AUTOCONNECT AUTOCONNECT-PRIORITY READONLY DBUS-PATH ACTIVE DEVICE STATE ACTIVE-PATH SLAVE
 Wired connection 1 b5405fe6-c553-3491-a172-711c8a3e1717 802-3-ethernet 1518202258 Fri 09 Feb 2018 10:50:58 AM PST yes 4294966297 no /org/freedesktop/NetworkManager/Settings/1 yes enxa44cc88a6c8b activated /org/freedesktop/NetworkManager/ActiveConnection/2 --
nmcli-dev:
 DEVICE TYPE STATE DBUS-PATH CONNECTION CON-UUID CON-PATH
 enxa44cc88a6c8b ethernet connected /org/freedesktop/NetworkManager/Devices/2 Wired connection 1 b5405fe6-c553-3491-a172-711c8a3e1717 /org/freedesktop/NetworkManager/ActiveConnection/2
 wlp2s0 wifi disconnected /org/freedesktop/NetworkManager/Devices/3 -- -- --
 lo loopback unmanaged /org/freedesktop/NetworkManager/Devices/1 -- -- --
nmcli-nm:
 RUNNING VERSION STATE STARTUP CONNECTIVITY NETWORKING WIFI-HW WIFI WWAN-HW WWAN
 running 1.8.4 connected started full enabled enabled enabled enabled enabled