Update from 10.0.3 to 11.0.2 failed

Nextcloud version (eg, 10.0.2): 11.0.2
Operating system and version (eg, Ubuntu 16.04): hosted webspace under Debian 2.6.32
Apache or nginx version (eg, Apache 2.4.25): netcup doesn’t tell
PHP version (eg, 5.6):5.6.30
Is this the first time you’ve seen this error?: y

Can you reliably replicate it? (If so, please outline steps): n

The issue you are facing:

The day before, I updated from 9.1.3 to 10.0.3 without problems.
When updaten from 10.0.3 to 11.0.2 the script stopped with some error, I don’t remember.
According to the logfile, it was at end of step 8:
2017-03-08T21:30:47+0100 putNuNOig8 [info] startStep(“8”)
2017-03-08T21:30:47+0100 putNuNOig8 [info] deleteOldFiles()
2017-03-08T21:30:50+0100 putNuNOig8 [info] config sample exists
2017-03-08T21:30:50+0100 putNuNOig8 [info] thmes README exists
2017-03-08T21:31:09+0100 putNuNOig8 [info] end of deleteOldFiles()
2017-03-08T21:31:09+0100 putNuNOig8 [info] endStep(“8”)
2017-03-10T16:58:25+0100 A8IYX4seHV [info] request to updater
2017-03-10T16:58:25+0100 A8IYX4seHV [info] currentStep()
2017-03-10T16:58:25+0100 A8IYX4seHV [info] Step 8 is in state “end”.
2017-03-10T16:58:25+0100 A8IYX4seHV [info] show HTML page
2017-03-10T16:58:25+0100 A8IYX4seHV [info] current version: 9.1.3 build time:

The installation is dead now.
Could anybody pls help, how to recover (at least the DB) without new installation?
Thanks for Your assistance!

The output of your Nextcloud log in Admin > Logging: not available

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

<?php $CONFIG = array ( 'instanceid' => 'ocehrd19m0gm', 'passwordsalt' => '***', 'secret' => '***', 'trusted_domains' => array ( 0 => 'd-***.de', ), 'datadirectory' => '/var/www/vhosts/hosting7651.af949.netcup.net/httpdocs/d-mcet/cloud/data', 'overwrite.cli.url' => 'https://d-***.de/cloud', 'dbtype' => 'sqlite3', 'version' => '', 'logtimezone' => 'UTC', 'installed' => true, 'updater.secret' => '***', 'maintenance' => true, 'theme' => '', 'loglevel' => 2, ); The output of your Apache/nginx/system log in `/var/log/____`: not available

It would be great to have more information. Did you check the nextcloud-logfile (in the data-folder).

Kernel version 2.6.32? That would be Debian squeeze, which ended security support in 2014 (and a long term support for some packages until February 2016).

Hello and thanks for your patience

the nextcloud.log contains only logs about user actions, nothing

meanwhile I’m trying to get more information about the OS where my site
is hosted…