I finally solved it. The official documentation is missing important informations and is not up to date.
I had to include my vhost configuration file /etc/apache2/vhost.d/wp-intranet.conf in /etc/apache2/httpd.conf
IncludeOptional /etc/apache2/vhosts.d/wp-intranet.conf
Then I noticed that I am unable to restart the service apache2.
Job for apache2.service failed because the control process exited with
error code. See "systemctl status apache2.service" and "journalctl
-xe" for details.
I executed systemctl status apache2.service
and got:
● apache2.service - The Apache Webserver
Loaded: loaded (/usr/lib/systemd/system/apache2.service; enabled; vendor preset: disabled)
Active: failed (Result: exit-code) since Tue 2018-07-10 12:59:07 CEST; 10s ago
Process: 2017 ExecStop=/usr/sbin/start_apache2 -DSYSTEMD -DFOREGROUND -k graceful-stop (code=exited, status=1/FAILURE)
Process: 7622 ExecReload=/usr/sbin/start_apache2 -DSYSTEMD -DFOREGROUND -k graceful (code=exited, status=0/SUCCESS)
Process: 2008 ExecStart=/usr/sbin/start_apache2 -DSYSTEMD -DFOREGROUND -k start (code=exited, status=1/FAILURE)
Main PID: 2008 (code=exited, status=1/FAILURE)
Jul 10 12:59:07 intern start_apache2[2008]: AH00526: Syntax error on line 8 of /etc/apache2/vhosts.d/wp-i...onf:
Jul 10 12:59:07 intern start_apache2[2008]: Invalid command 'Order', perhaps misspelled or defined by a m...tion
Jul 10 12:59:07 intern systemd[1]: apache2.service: Main process exited, code=exited, status=1/FAILURE
Jul 10 12:59:07 intern start_apache2[2017]: AH00548: NameVirtualHost has no effect and will be removed in...f:41
Jul 10 12:59:07 intern start_apache2[2017]: AH00526: Syntax error on line 8 of /etc/apache2/vhosts.d/wp-i...onf:
Jul 10 12:59:07 intern start_apache2[2017]: Invalid command 'Order', perhaps misspelled or defined by a m...tion
Jul 10 12:59:07 intern systemd[1]: apache2.service: Control process exited, code=exited status=1
Jul 10 12:59:07 intern systemd[1]: Failed to start The Apache Webserver.
Jul 10 12:59:07 intern systemd[1]: apache2.service: Unit entered failed state.
Jul 10 12:59:07 intern systemd[1]: apache2.service: Failed with result 'exit-code'.
Hint: Some lines were ellipsized, use -l to show in full.
So I figured out that the virtual host configuration from the official documentation has syntax errors. I had to change it to this:
<VirtualHost *:80>
ServerName intranet.mycompany.de
DocumentRoot /srv/www/vhosts/wp-intranet
ServerAdmin edward.black@mycompany.de
ErrorLog /var/log/apache2/intranet.mycompany.de_errorlog
CustomLog /var/log/apache2/intranet.mycompany.de_customlog common
<Directory "/srv/www/vhosts/wp-intranet">
#Order allow,deny
AllowOverride All
#Allow from all
Require all granted
</Directory>
</VirtualHost>
Now I was able to restart apache2 and if I navigate to http://intranet.mycompany.de/
then the wordpress site opens!