'404 Not found' after successful setup

Steps to reproduce

  1. Download
  2. Install from .rpm
  3. Launch.

Expected behaviour

Make it work...

Actual behaviour

Can't reach login page, files not found

Server configuration

Operating system: CentOS Linux release 7.4.1708

Web server: Apache/2.4.6 (CentOS) OpenSSL/1.0.2k-fips mod_fcgid/2.3.9

Database: MariaDB 5.5.56

PHP version: 7.0.10

ownCloud version: (see ownCloud admin page) 10.0.4

Updated from an older ownCloud or fresh install: fresh install

Where did you install ownCloud from:

Signing status (ownCloud 9.0 and above):

not found

The content of config/config.php:

<?php
$CONFIG = array (
  'instanceid' => 'och7ojpvog5w',
  'debug' => true,
  'loglevel' => 0,
  'passwordsalt' => 'salt',
  'secret' => 'secret',
  'trusted_domains' => 
  array (
    0 => 'my_IP',
  ),
  'datadirectory' => '/mnt/docs',
  'overwrite.cli.url' => 'http://my_IP/owncloud',
  'dbtype' => 'mysql',
  'version' => '10.0.4.4',
  'dbname' => 'owncloud_docs',
  'dbhost' => 'localhost',
  'dbtableprefix' => 'oc_',
  'dbuser' => 'oc_user',
  'dbpassword' => 'mypass',
  'logtimezone' => 'UTC',
  'installed' => true,
);

sudo -u www-data php occ config:list system

php: command not found

List of activated apps:

Are you using external storage, if yes which one: NFS

Are you using encryption: No

Are you using an external user-backend, if yes which one: No

Client configuration

Browser: Firefox 52.7.3

Operating system: Debian 9

Logs

Web server error log

[Fri Apr 13 09:32:20.933546 2018] [mpm_prefork:notice] [pid 6436] AH00170: caught SIGWINCH, shutting down gracefully
[Fri Apr 13 09:32:22.088014 2018] [core:notice] [pid 18231] SELinux policy enabled; httpd running as context system_u:system_r:httpd_t:s0
[Fri Apr 13 09:32:22.089805 2018] [suexec:notice] [pid 18231] AH01232: suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[Fri Apr 13 09:32:22.127138 2018] [alias:warn] [pid 18231] AH00671: The Alias directive in /etc/httpd/conf.d/manual.conf at line 5 will probably never match because it overlaps an earlier Alias.
[Fri Apr 13 09:32:22.127386 2018] [alias:warn] [pid 18231] AH00671: The Alias directive in /etc/httpd/conf.d/welcome.conf at line 18 will probably never match because it overlaps an earlier Alias.
[Fri Apr 13 09:32:22.127406 2018] [alias:warn] [pid 18231] AH00671: The Alias directive in /etc/httpd/conf.d/welcome.conf at line 19 will probably never match because it overlaps an earlier Alias.
[Fri Apr 13 09:32:22.127414 2018] [alias:warn] [pid 18231] AH00671: The Alias directive in /etc/httpd/conf.d/welcome.conf at line 20 will probably never match because it overlaps an earlier Alias.
[Fri Apr 13 09:32:22.127422 2018] [alias:warn] [pid 18231] AH00671: The Alias directive in /etc/httpd/conf.d/welcome.conf at line 21 will probably never match because it overlaps an earlier Alias.
[Fri Apr 13 09:32:22.127441 2018] [alias:warn] [pid 18231] AH00671: The Alias directive in /etc/httpd/conf.d/welcome.conf at line 22 will probably never match because it overlaps an earlier Alias.
AH00558: httpd: Could not reliably determine the server's fully qualified domain name, using localhost.localdomain. Set the 'ServerName' directive globally to suppress this message
[Fri Apr 13 09:32:22.128456 2018] [auth_digest:notice] [pid 18231] AH01757: generating secret for digest authentication ...
[Fri Apr 13 09:32:22.129874 2018] [lbmethod_heartbeat:notice] [pid 18231] AH02282: No slotmem from mod_heartmonitor
[Fri Apr 13 09:32:22.139134 2018] [mpm_prefork:notice] [pid 18231] AH00163: Apache/2.4.6 (CentOS) OpenSSL/1.0.2k-fips mod_fcgid/2.3.9 configured -- resuming normal operations
[Fri Apr 13 09:32:22.139186 2018] [core:notice] [pid 18231] AH00094: Command line: '/usr/sbin/httpd -D FOREGROUND'

ownCloud log (data/owncloud.log)

empty

Browser log

Insert your browser log here, this could for example include:

a) The javascript console log
b) The network log 
c) ...

Additionally, I tried to reach login page with SELinux in permissive mode. Doesn't help.

I think you're missing the Apache configuration shown e.g. here:

https://doc.owncloud.org/server/latest/admin_manual/installation/source_installation.html#configure-apache-web-server