Here are the steps
sudo apt-get install software-properties-common
sudo apt-key adv --recv-keys --keyserver hkp://keyserver.ubuntu.com:80 0xF1656F24C74CD1D8
$ sudo add-apt-repository 'deb [arch=amd64,i386] http://mirror.fibergrid.in/mariadbrepo/10.1/ubuntu xenial main'
sudo apt-get update
sudo apt-get install mariadb-server
sudo: /etc/sudoers.d is world writable Reading package lists... Done Building dependency tree Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: mariadb-server : Depends: mariadb-server-10.1 (= 10.1.14+maria-1~trusty) but it is not going to be installed E: Unable to correct problems, you have held broken packages.