Hi Jozef,
Maybe I can help, I've been thru the same problem as you (also on Ubuntu 16.04) and I figured out the script that runs identity is failing due to a missing JAVA_HOME environment variable.
In order to fix that, issue this command
```
sudo service gluu-server-3.0.1 login
```
That will put you on the chroot environment. Once there, include the JAVA_HOME like this
```
vi /etc/environment
```
Add this line below the PATH line:
> JAVA_HOME="/opt/jre"
After that, you can either manually start identity or simply edit the chroot and restart gluu-server and its gonna work.
Let me know if you have luck, coz I had some troubles right after that. Apache is running into an infinite redirect.
Cheers,