On my laptop Lenovo B50-45,I use my favorite OS Ubuntu Mate 16.04.3.For the Internet I do not have router,instead I use,equipment i got it private provider.With him I assemble myself,contract on 2 years.But last 20-30 days he appeared issue with DNS,I asked when will to be solved…the answer we are working on it???I had find a solution how in Ubuntu correct change DNS,to go again onlayn.On the google and ask Ubuntu,is many answers bath do not work for mee.The only solution which works for mee iss…install Mate then(beause no inthernet) no to install updates,first of all open therminal and type gksudo pluma /etc/dhcp/dhclient.conf and find where wrote prepend domain-name-servers and there change to 8.8.8.8,8.8.4.4;(google public dns) save that file…reboot pc.And now inthernet working,but please write me how to correct changes dns in Ubuntu.And is there method to see in terminal,which currently dns i running.I sk this beause auth there is a zilion answers,but i think only one is regular.
P.S. Sory to my bad eanglis,this is writen with litle help google translate
Hi @milewap, 16.04 really hides their DNS servers behind dnsmasq, networkmanager and early systemd-resolve. I get rid of those personally but in a stock VM I did find this info works:
nmcli device show | grep DNS
This is changing in later versions like 17.04 when systemd-resolve takes over dnsmasq local caching server.
I olso @Bill_MI right now,i found type this cat /etc/resolv.conf and you see dns.My terminal right now after cat /etc/resolv.conf mirko@mirko-Lenovo-B50-45:~$ cat /etc/resolv.conf
Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
DO NOT EDIT THIS FILE BY HAND – YOUR CHANGES WILL BE OVERWRITTEN
nameserver 8.8.8.8
nameserver 8.8.4.4
nameserver 8.8.8.8
nameserver 8.8.4.4mirko@mirko-Lenovo-B50-45:~$
Olso on this link http://www.techrepublic.com/article/how-to-prevent-ubuntu-from-overwriting-etcresolv-conf you find how to prevent overwriting hmmmm maybe also this link is useful https://sites.google.com/site/easylinuxtipsproject/7 .Whatever I’m successful chaged dns,and now i am back onlayn 
I would not opening new topic,I’ll write it here.I had reinstall OS(Ubuntu Mate 16.04.3 lts),I have a 2 wifi network adapters.One is factory built in laptop Lenovo b50-45…QCA9565 / AR9565 Wireless Network Adapter,and other is USB Realtek Kasens KS-G9000.After reinstall Realtek it works normally.But QCA9565 / AR9565 Wireless Network Adapter see network,and when I click to connect…on the screen comes out (7) The access point /org/freedesktop/NetworkManager/AccessPoint/5 was not in the scan list …wherein AccesPoint scan list in NetworkManager?And how to add AccesPoint,thank you for any kind of help.