After some more testing this appears to be something with apache2. The script directs me to http://<ip address>/fog/management to install the database scheme. And this is where I get the blank page. But if I use the hostname, http://<hostname>/fog/management then the content does appear and I am able to install the database scheme and use fog. After that, I can use either hostname or IP but it seems that for the initial database install, I must use the hostname.

@Sebastian-Roth I should have stated that this not completely a default Ubuntu install. My end goal is to install FOG from an ansible playbook. I install mariadb and apache2 from their playbooks. I tried reinstalling php and apache from the install script, but that results in an error 500 and no errors in /var/log/apache2/error.log. So I have stuck with my install of apache and php.

I can connect to mysql and create the database:

 # mysql -u fogdb -h localhost -p
Enter password: 
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 7536
Server version: 10.1.25-MariaDB-1~xenial mariadb.org binary distribution

Copyright (c) 2000, 2017, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [(none)]> CREATE DATABASE fog
    -> 

Server

• FOG Version: 1.4.4
• OS: Ubuntu 16.04

Description

Issue: When the install tells me to go the webpage and install the database schema, there is not content. The headers are there but there is not button to install.

I was looking at this post describing the same issue. I moved /var/www, re-ran the installer and still same issue. So I looked at /var/log/apache2/error.log and whenever I connected this line was entered:
PHP Warning: ini_set() has been disabled for security reasons in /var/www/fog/lib/fog/fogcore.class.php on line 241
So then I found this which told me to enable ini_set. I did so by removing ini_set from the disabled list in /etc/php/7.0/apache2/php.ini. Rerun the installer and no luck. Now /var/log/apache2/error.log contains
PHP Warning: session_start(): open( /var/www/tmp/sess_...) failed: No such file or directory
I found that /var/www/tmp/ did not exist so I created it and chown-ed chgrp-ed it to www-data.
…and no go.

Now /var/log/apache2/error.log contains no more errors and I still can’t install the database.

Is there another log file I need to be looking at? Or what else could be causing the page to not load?