Nextcloud Host violates local access rules Error and Apache AH00558 Error

I have just finished manually installing the latest version of Nextcloud onto my file server PC running the Ubuntu Server 22.04.4 OS. It is a direct to metal installation of Nextcloud. In other words, it is not a SNAP or a Docker Portainer installation. Lastly, I followed the install instructions outlined in the YouTube video below:

My Apache2 installation is brand new and the problem is as follow. When I run this command: sudo systemctl status apache2 I get the WARNING shown below in my SSH terminal:

AH00558: apache2: Could not reliably determine the server’s fully qualified domain name, using Set the ‘ServerName’ directive globally to suppress this message

How do I fix this AH00558 error? And what does it mean? I ask because I strongly suspect this AH00558 error is behind a second error I am getting in my builtin Nextcloud Logging window shown below:

Host was not connected to because it violates local access rules.

Below I have included both my PHP.conf file and my Nextcloud.conf file. My hope is somebody in this forum can take a look at the two files below and let me know if a problem exists I need to fix:

MY PHP.conf file below:

> <?php
> $CONFIG = array (
>   'instanceid' => 'XXXXXXXXXXXXXXXXX',
>   'passwordsalt' => 'XXXXXXXXXXXXXXXXXXXXXXXXX',
>   'trusted_domains' =>
>   array (
>     0 => '',
>   ),
>   'datadirectory' => '/mnt/myssd/nextcloud/data',
>   'dbtype' => 'mysql',
>   'version' => '',
>   'overwrite.cli.url' => '',
>   'dbname' => 'nextcloud',
>   'dbhost' => 'localhost',
>   'dbport' => '',
>   'dbtableprefix' => 'oc_',
>   'mysql.utf8mb4' => true,
>   'dbuser' => 'XXXXXXXXXXXXXX',
>   'dbpassword' => 'XXXXXXXXXXXXXX',
>   'installed' => true,
>   'memcache.local' => '\\OC\\Memcache\\APCu',
>   'memcache.distributed' => '\\OC\\Memcache\\Memcached',
>   'memcache.locking' => '\\OC\\Memcache\\Memcached',
>   'default_phone_region' => 'US',
>   'maintenance_window_start' => 1,
>   'maintenance' => false,
>   'allow_local_remote_servers' => true,
> );

MY Nextcloud.conf file below:

  GNU nano 6.2                                    nextcloud.conf
<VirtualHost *:80>
        Protocols h2 h2c http/1.1
        DocumentRoot /var/www/nextcloud

        <IfModule mod_headers.c>
          Header always set Strict-Transport-Security "max-age=15552000; includeSubDomains"

        <FilesMatch \.php$>
          SetHandler "proxy:unix:/var/run/php/php8.2-fpm.sock|fcgi://localhost"

        <Directory /var/www/nextcloud/>
                Satisfy Any
                Require all granted
                Options FollowSymlinks MultiViews
                AllowOverride All
                <IfModule mod_dav.c>
                        Dav off

        ErrorLog /var/log/apache2/nextcloud-error.log
        CustomLog /var/log/apache2/nextcloud-access.log common

The apache message is a warning (apache is still running, it just tells you some things might be not ideal, were forgotten etc, but it does not prevent apache from running what an error would do):

what is the builtin logging window, in the client, terminal, browser gui?

Do you find this error in your apache logs? (/var/log/apache2/…)?

Tflidd, thank you for your post. Executing the command below in my terminal fixed my AH00558 error.
echo "ServerName" >> /etc/apache2/apache2.conf

Nextcloud for some reason I don’t understand was having a problem with host and therefore had to be added to the apache2.conf file. The YouTube video I followed totally skipped over this detail.

As to the second error, to answer your question I am referring to the Log Reader which is located within the Admintration section of Nextcloud. This problem still has me stumped and I cannot find any solution for it in this entire Nextcloud website support section.

In short, the error involves my Window10 client PC with a IP number. My Nextcloud Ubuntu server does no like the remote address which belongs to my Windows client PC.

Do you know how to wipe the Nextcloud Log Reader? It will help me a lot if I could wipe the Log Reader clean so I could know what errors are still active.