The link you provided put me on the right track.  At this url there are three answers to the question how to disable systemd-resolved in Ubuntu 17.04.  The first answer says it also works for Ubuntu 18.04.  The instructions in the first answer fixed the problem for me. https://askubuntu.com/questions/907246/how-to-disable-systemd-resolved-in-ubuntu Thanks to everyone who replied. On 12/7/18 10:21 PM, Michael Butash wrote: > It's using a local dnsmasq server for caching, akin to what windoze > does, only it uses an external service and not hidden behind the > scenes.  You can remove dnsmasq, usually at least, and resolve direct > against your dns servers, I usually start by removing the package, as > I've had enough issues with it being weird, I tend to not like using it. > > I'm presuming 192.168.1.4 and 192.168.1.1 are valid dns servers? > > I'm having a weird issue that network manager has a bad dns stuck in > it somewhere that keeps causing me site delays when it'll randomly put > it back into my dns servers list as first.  It's not a setting I can > find, or anything in /etc/, I'm thinking something in gconf settings > lost, but might be something similar there if that 192.168.1.4 servers > isn't valid. > > This might be useful to see what servers dnsmasq is using. > > https://askubuntu.com/questions/556852/how-can-i-tell-which-dns-servers-dnsmasq-is-using > > -mb > > > On Fri, Dec 7, 2018 at 7:44 PM Jim > wrote: > > Today I noticed a problem when I use Thunderbird to check my email > on my > Kubuntu 18.04 box.  I got  the following error in Thunderbird: > Failed to > connect to imap.comcast.net However it > will connect to > imap.comcast.net . I also couldn't ping > imap.comcast.net . > > delboy@ladmo:~$ ping imap.comcast.net > ping: imap.comcast.net : Name or service > not known > delboy@ladmo:~$ > > In Network manager I have  the following DNS servers in this order: > 192.168.1.4 192.168.1.1, 8.8.8.8 8.8.4.4.  I found this in > /etc/resolv.conf > > # Generated by NetworkManager > nameserver 127.0.0.53 > > If I change 127.0.0.53 to one of the DNS servers I have in Network > Manager, Thunderbird works again, but I'm not able to ping > imap.comcast.net . I get the same error I > mentioned earlier.  I really > don't care if I can ping it or not as long as Thunderbird can > connect to > it.   However when I reboot or restart Network Manager, > resolv.conf goes > back to 127.0.0.3. > > Is there some bug with Network Manager or has comcast manged to > screw up > something? > > thanks > > --------------------------------------------------- > PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org > > To subscribe, unsubscribe, or to change your mail settings: > https://lists.phxlinux.org/mailman/listinfo/plug-discuss > > > --------------------------------------------------- > PLUG-discuss mailing list -PLUG-discuss@lists.phxlinux.org > To subscribe, unsubscribe, or to change your mail settings: > https://lists.phxlinux.org/mailman/listinfo/plug-discuss