Internal server error after upgrade to nextcloud15

Hello,
its really strange, everytime I try to update(web-installer) any nextcloud installation…
…it fails, maintenance mode.
Then I set all file permissions to www-data750, I dont even know how to repair this mess, switch back to the old version…

any help would be really apprecciated!
at least I can accesss the nextcloud installation viassh now and use the occ shell command! But that didnt help me till now.

(I searched the web and this forum a lot, but didnt get any further)

Nextcloud version (eg, 12.0.2): from 14 something to 15.0.5.3
Operating system and version (eg, Ubuntu 18.04): Kubuntu 18.04
Apache or nginx version (eg, Apache 2.4.25): apache 2.4.29
PHP version (eg, 7.1): php7.2

The issue you are facing:

Internal Server Error

The server encountered an internal error and was unable to complete your request.
Please contact the server administrator if this error reappears multiple times, please include the technical details below in your report.
More details can be found in the server log.

Is this the first time you’ve seen this error? (Y/N): N

Steps to replicate it:

  1. update from nc version 14 to nc version15

The output of your Nextcloud log in Admin > Logging:

cannot PASTE HERE, because I cannot log in. so I cannot show logs.

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

$CONFIG = array (
  'instanceid' => 'is this important?',
  'passwordsalt' => 'something strange',
  'secret' => 'secretthing',
  'trusted_domains' => 
  array (
    0 => '192.168.0.21',
    1 => 'domain',
  ),
  'openssl' => array(
        'config' => '/etc/ssl/openssl.cnf',
  ),

  'datadirectory' => '/var/www/nextcloud/data',
  'dbtype' => 'mysql',
  'version' => '15.0.5.3',
  'overwrite.cli.url' => '',
  'dbname' => 'nextcloud_db',
  'dbhost' => 'localhost',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'dbuser' => '',
  'dbpassword' => '',
  'installed' => true,
  'mail_from_address' => '',
  'mail_smtpmode' => 'smtp',
  'mail_domain' => '',
  'mail_smtpauthtype' => 'LOGIN',
  'mail_smtpauth' => 1,
  'mail_smtpport' => '465',
  'mail_smtphost' => 'server',
  'mail_smtpsecure' => 'ssl',
  'mail_smtpname' => 'mailadress',
  'mail_smtppassword' => 'secret',
  'maintenance' => false,
  'updater.secret' => 'yxz',
  'theme' => '',
  'loglevel' => 0,
);

The output of your Apache/nginx/system log in /var/log/____: apache-access-log


95.90.73.50 - simon [11/Mar/2019:18:40:24 +0100] "PROPFIND /nextcloud/remote.php/dav/files/simon/ HTTP/1.1" 207 4426 "-" "Mozilla/5.0 (Linux) mirall/2.5.1git (Nextcloud)"
95.90.73.50 - simon [11/Mar/2019:18:40:35 +0100] "PROPFIND /nextcloud/remote.php/dav/files/simon/ HTTP/1.1" 207 4425 "-" "Mozilla/5.0 (Linux) mirall/2.5.1git (Nextcloud)"
95.90.73.50 - simon [11/Mar/2019:18:40:56 +0100] "PROPFIND /nextcloud/remote.php/dav/files/simon/ HTTP/1.1" 207 4426 "-" "Mozilla/5.0 (Linux) mirall/2.5.1git (Nextcloud)"
95.90.73.50 - simon [11/Mar/2019:18:41:05 +0100] "PROPFIND /nextcloud/remote.php/dav/files/simon/ HTTP/1.1" 207 4425 "-" "Mozilla/5.0 (Linux) mirall/2.5.1git (Nextcloud)"
95.90.73.50 - simon [11/Mar/2019:18:41:28 +0100] "PROPFIND /nextcloud/remote.php/dav/files/simon/ HTTP/1.1" 207 4426 "-" "Mozilla/5.0 (Linux) mirall/2.5.1git (Nextcloud)"
95.90.73.50 - simon [11/Mar/2019:18:41:35 +0100] "PROPFIND /nextcloud/remote.php/dav/files/simon/ HTTP/1.1" 207 4425 "-" "Mozilla/5.0 (Linux) mirall/2.5.1git (Nextcloud)"
95.90.73.50 - simon [11/Mar/2019:18:41:37 +0100] "GET /nextcloud/ocs/v2.php/apps/notifications/api/v2/notifications?format=json HTTP/1.1" 304 266 "-" "Mozilla/5.0 (Linux) mirall/2.5.1git (Nextcloud)"
95.90.73.50 - simon [11/Mar/2019:18:42:00 +0100] "PROPFIND /nextcloud/remote.php/dav/files/simon/ HTTP/1.1" 207 4426 "-" "Mozilla/5.0 (Linux) mirall/2.5.1git (Nextcloud)"
95.90.73.50 - simon [11/Mar/2019:18:42:05 +0100] "PROPFIND /nextcloud/remote.php/dav/files/simon/ HTTP/1.1" 207 1160 "-" "Mozilla/5.0 (Linux) mirall/2.5.1git (Nextcloud)"

Apache error.log

[Mon Mar 11 04:06:01.522557 2019] [php7:error] [pid 1869] [client 123.207.237.141:41459] script '/var/www/html/51.php' not found or unable to stat
[Mon Mar 11 04:06:02.333739 2019] [php7:error] [pid 1869] [client 123.207.237.141:41459] script '/var/www/html/cadre.php' not found or unable to stat
[Mon Mar 11 04:06:02.661273 2019] [php7:error] [pid 1869] [client 123.207.237.141:41459] script '/var/www/html/mm.php' not found or unable to stat
[Mon Mar 11 04:06:03.006820 2019] [php7:error] [pid 1869] [client 123.207.237.141:41459] script '/var/www/html/test.php' not found or unable to stat
[Mon Mar 11 04:06:03.833622 2019] [php7:error] [pid 1869] [client 123.207.237.141:41459] script '/var/www/html/1q.php' not found or unable to stat
[Mon Mar 11 04:06:04.197335 2019] [php7:error] [pid 1869] [client 123.207.237.141:41459] script '/var/www/html/1111.php' not found or unable to stat
[Mon Mar 11 04:06:04.876350 2019] [php7:error] [pid 1869] [client 123.207.237.141:41459] script '/var/www/html/errors.php' not found or unable to stat
[Mon Mar 11 04:06:05.221749 2019] [php7:error] [pid 1869] [client 123.207.237.141:41459] script '/var/www/html/q.php' not found or unable to stat
[Mon Mar 11 04:06:05.582611 2019] [php7:error] [pid 1869] [client 123.207.237.141:41459] script '/var/www/html/lanyecn.php' not found or unable to stat
[Mon Mar 11 04:06:05.946155 2019] [php7:error] [pid 1869] [client 123.207.237.141:41459] script '/var/www/html/mybestloves.php' not found or unable to stat
[Mon Mar 11 04:06:06.761857 2019] [php7:error] [pid 1869] [client 123.207.237.141:41459] script '/var/www/html/index.php' not found or unable to stat
[Mon Mar 11 14:11:16.975666 2019] [php7:error] [pid 1865] [client 109.41.128.198:19679] script '/var/www/html/index.php' not found or unable to stat

set occ maintenance mode on and tried to repair (worked fine yesterday, seems to be broken now, output will follow)

´´´
sudo -u www-data php occ maintenance:repair
Nextcloud is in maintenance mode - no apps have been loaded

Failed to load repair step for audioplayer: Repair step ‘OCA\audioplayer\Migration\Migration’ is unknown
Failed to load repair step for dav: Repair step ‘OCA\DAV\Migration\FixBirthdayCalendarComponent’ is unknown
Failed to load repair step for dav: Repair step ‘OCA\DAV\Migration\CalDAVRemoveEmptyValue’ is unknown
Failed to load repair step for dav: Repair step ‘OCA\DAV\Migration\BuildCalendarSearchIndex’ is unknown
Failed to load repair step for dav: Repair step ‘OCA\DAV\Migration\RefreshWebcalJobRegistrar’ is unknown
Failed to load repair step for dav: Repair step ‘OCA\DAV\Migration\RemoveClassifiedEventActivity’ is unknown
Failed to load repair step for encryption: Repair step ‘OCA\Encryption\Migration\SetMasterKeyStatus’ is unknown
Failed to load repair step for files_sharing: Repair step ‘OCA\Files_Sharing\Migration\OwncloudGuestShareType’ is unknown
Failed to load repair step for files_sharing: Repair step ‘OCA\Files_Sharing\Migration\SetPasswordColumn’ is unknown
Failed to load repair step for oauth2: Repair step ‘OCA\OAuth2\Migration\SetTokenExpiration’ is unknown
Failed to load repair step for twofactor_backupcodes: Repair step ‘OCA\TwoFactorBackupCodes\Migration\CheckBackupCodes’ is unknown

  • Repair MySQL collation
    • All tables already have the correct collation -> nothing to do
  • Repair mime types
  • Clean tags and favorites
    • 0 tags of deleted users have been removed.
    • 0 tags for delete files have been removed.
    • 0 tag entries for deleted tags have been removed.
    • 0 tags with no entries have been removed.
  • Repair invalid shares
  • Remove shares of a users root folder
  • Move .step file of updater to backup location
  • Fix potential broken mount points
    • No mounts updated
  • Repair invalid paths in file cache
  • Add log rotate job
  • Clear frontend caches
    • Image cache cleared
    • SCSS cache cleared
    • JS cache cleared
  • Clear every generated avatar on major updates
  • Add preview background cleanup job
  • Queue a one-time job to cleanup old backups of the updater
  • Repair pending cron jobs
    • No need to repair pending cron jobs.
  • Extract the vcard uid and store it in the db
    ``

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