When I ssh into an Ubuntu server which is running a live web site, I see the following messages:
2 packages can be updated.
2 updates are security updates.
At that point, I can update and upgrade with the following command:
sudo apt-get update
sudo apt-get upgrade
Is it recommended to run the above on a live server with mission critical applications?
apt-get updatedoes not have a--just-printoption.apt-get updatedownloads the package lists from the repositories and "updates" them to get information on the newest versions of packages and their dependencies. A great description of these commands can be found here – PanPipes Aug 02 '16 at 20:58