In this guide I will be showing you how you can run the commands on Ubuntu 15.04 to update the packages along with the distribution on the system. It is always a good idea to make sure that a server is up to date.
Updating Package List
To update the list of packages on the server run
sudo apt-get update
To update all of the packeges on the server to their latest releases run
sudo apt-get upgrade
To upgrade the distribution to the latest version, you can run
sudo apt-get dist-upgrade
You can run all of these using the following command:
sudo apt-get update sudo apt-get upgrade sudo apt-get dist-upgrade
When you do so, you will get asked if you want to continue, just type y and then press enter.