[R-sig-Debian] "Failed-to-restart-avahi-dnsconfd-service" error when I try to install R binary.

[Rolf Turner]

In the past I have been told, very firmly, by those who are 
knowledgeable that when upgrading R I should install the binary R 
provided for the Ubuntu OS.

Being a docile and biddable young ( :-) ) fellow, I have tried to do so,
following the instructions made available at:

    https://cran.r-project.org/bin/linux/ubuntu/README.html

I have made sure that the line

     deb https://cloud.r-project.org/bin/linux/ubuntu bionic-cran35/

is present in my /etc/apt/sources.list file and I  then do:

     sudo apt-get update

(which seems to go OK) and then:

     sudo apt-get install r-base

At this point

(a) I get told “r-base is already the newest version (3.5.2-1bionic).” 
(although when I start R it is apparent that I am running version 3.5.1)

(This puzzles me completely.)

(b) I then get asked if I want to continue (anyway); I answer “y” and 
then get an error:

> Setting up avahi-dnsconfd (0.7-3.1ubuntu1.1) ...
> Failed to restart avahi-dnsconfd.service: Unit avahi-daemon.service is masked.
> invoke-rc.d: initscript avahi-dnsconfd, action "restart" failed.
> ● avahi-dnsconfd.service - Avahi DNS Configuration Daemon
>    Loaded: loaded (/lib/systemd/system/avahi-dnsconfd.service; enabled; vendor preset: enabled)
>    Active: inactive (dead)

(And a bunch more bumff.)  Then everything comes to a shuddering halt.

It's quite possible that there is a simple fix, but I have no idea what 
this fix might be.  (It is also quite possible that something 
complicated is needed.)

Can anyone please enlighten me? I have no idea what further information 
would be useful but am of course happy to provide (do my best to 
provide) any such information that I am asked for.

I am running the Mate Desktop Environment 1.20.1 under Ubuntu 18.04.

cheers,

Rolf Turner

P.S.  I have also posted a question about this matter on the Ubuntu Mate 
Community web site.  I hope that asking this question in two places is 
not too terribly anti-social.

R. T.

-- 
Honorary Research Fellow
Department of Statistics
University of Auckland
Phone: +64-9-373-7599 ext. 88276