How to add a PPA on a server?

You can simply add the add-apt-repository command. In 13.10 and later, you also need to run this command:

sudo apt-get install software-properties-common

Side note: in 11.04 they added a symlink to add-apt-repository so it can be run as apt-add-repository which totally makes more sense to me. Everything else apt starts with "apt".

NOTE: It's part of the python-software-properties package (before 13.10):

sudo apt-get install python-software-properties

Let me teach you how to fish. apt-file enables you to find out which package provides a given file. dpkg -S does the same thing, but only for installed packages. apt-file works whether or not the package has been installed.

So, first you install apt-file: sudo apt-get install apt-file. You then need to update its information, just as you have to with apt-get: sudo apt-file update. Now it's ready for use:

$ apt-file search add-apt-repository
python-software-properties: /usr/bin/add-apt-repository
python-software-properties: /usr/share/man/man1/add-apt-repository.1.gz

So, in this case the next thing to do would be to install python-software-properties.

It is not necessarily the best answer, but this will function:

The old-fashioned way (pre Ubuntu 9.10, they call it) of editing /etc/apt/sources.list still works. You will also need to get the GPG key on the system manually.

On older (pre 9.10) Ubuntu systems:

Step 1: Visit the PPA's overview page in Launchpad. Look for the heading that reads Adding this PPA to your system and click the Technical details about this PPA link.

Step 2: Use the Display sources.list entries drop-down box to select the version of Ubuntu you're using.

Step 3: You'll see that the text-box directly below reads something like this:

deb http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu jaunty main
deb-src http://ppa.launchpad.net/gwibber-daily/ppa/ubuntu jaunty main

Copy those lines.

Step 4: Open a terminal and type:

sudo gedit /etc/apt/sources.list

This will open a text editor containing the list of archives that your system is currently using. Scroll to the bottom of the file and paste the lines you copied in the step above.

Save the file and exit the text editor.

Step 5: Back on the PPA's overview page, look for the Signing key heading. You'll see something like:

1024R/72D340A3 (What is this?)

Copy the portion after the slash but not including the help link; e.g. just 72D340A3.

Step 6: Now you need to add that key to your system so Ubuntu can verify the packages from the PPA. In your terminal, enter:

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 72D340A3

(Replace 72D340A3 with whatever you copied in the step 5.)

This will now pull down the PPA's key and add it to your system.

Step 7: Now, as a one-off, you should tell your system to pull down the latest list of software from each archive it knows about, including the PPA you just added:

sudo apt-get update

Now you're ready to start installing software from the PPA!