How to Enable and Disable Root Login in Ubuntu [for those 32 individuals asked this in the last 12 months]

OK, well, this is not one of those post I’d like to publish, but just counted how many time people asked this question in the last 12 months. I found 32 emails.
I’ll give you the simplest, permanent UNSAFE solution. Use this if you need after finishing you server installation.DO NOT LEAVE ENABLED ON A LIVE RUNNING SERVER.
There are options to enable it temporarily, or set and expire time.
Be safe!

lnrsoft@server:~$ sudo su
[sudo] password for lnrsoft: 
root@server:/home/lnrsoft# sudo passwd root
New password: 
Retype new password: 
passwd: password updated successfully
root@server:/home/lnrsoft# whoami