Gfilui

I have been trying to update Nginx to it's latest version in my ubuntu server.

So, I tried with this command:

sudo add-apt-repository ppa:nginx/stable

sudo apt-get update

sudo apt-get install nginx

But the result showing that Nginx is already in the newest version (1.12.2-0+xenial0)

Here's the output of sudo apt-cache policy nginx

Pre-Built Packages for Mainline version Ubuntu 16.04

For Ubuntu, in order to authenticate the nginx repository signature and to eliminate warnings about missing PGP key during installation of the nginx package, it is necessary to add the key used to sign the nginx packages and repository to the apt program keyring. Please copy/paste into text file and rename nginx_signing.key in Home Directory this key from our web site, and add it to the apt program keyring with the following command:

sudo apt-key add nginx_signing.key

Append the following to the end of the /etc/apt/sources.list file:

sudo nano /etc/apt/sources.list

deb http://nginx.org/packages/mainline/ubuntu/ xenial nginx
deb-src http://nginx.org/packages/mainline/ubuntu/ xenial nginx

For Ubuntu then run the following commands:

sudo apt-get update 
sudo apt-get install nginx

SOURCE

1.12.2 is the current stable version of nginx.

If you want the mainline version of nginx you have to use the PPA ppa:nginx/development instead of ppa:nginx/stable