Automatic, unattended install of phpmyadmin

In this brave new world of infrastructure automation, being able to install a package without manual intervention is a bare necessity.

And, how difficult can it be, installing phpmyadmin, automatically, without manual intervention.

Of course this turned out to be slightly more difficult than I thought, and as I couldn't find a real good resource on the web I decided to put my findings in a blog. Possibly more as a future reminder for myself :-)

Installing packages such as phpmyadmin on Debian/Ubuntu is usually a breeze, thanks to the apt package manager. And by passing the -y option you can send yes to all questions that may arise in this setup.

Also,  Debian (and hence also Ubuntu) has for a long time the DEBIAN_FRONTEND parameter. By setting this to noninteractive, no questions will be asked.

# export DEBIAN_FRONTEND=noninteractive

# apt-get -q -y phpmyadmin

However, what to do with questions that really need some inputs, such as asking for the database password. Welcome to debconf-set-selections.

With debconf-set-selections you basically answer the questions that will be asked in the setup before the actual install.

So by running the following command, the main questions will be answered and then the actual install will proceed without that pesky blue screen:

echo 'phpmyadmin phpmyadmin/dbconfig-install boolean true' | debconf-set-selections
echo 'phpmyadmin phpmyadmin/app-password-confirm password your-app-pwd' | debconf-set-selections
echo 'phpmyadmin phpmyadmin/mysql/admin-pass password your-admin-db-pwd' | debconf-set-selections
echo 'phpmyadmin phpmyadmin/mysql/app-pass password your-app-db-pwd' | debconf-set-selections
echo 'phpmyadmin phpmyadmin/reconfigure-webserver multiselect apache2' | debconf-set-selections

Nice, but where do these variables come from? Welll, actually there are a lot more variables to play with, and if you really want to know run the following command after the install of the package:

debconf-get-selections | grep phpmyadmin

This will return all parameters for that particular package, most of them are self-explanatory.

For completeness, the debconf-utils package is needed, but luckily that installs with only the -y parameter provided.