<solved>NC13:Error 503 Service Unavailable, suddenly can't sync, can't download files or folders

ℹ️ Support
1

Nextcloud version (13.0.6):
Operating system and version (Debian 9):
Apache or nginx version (Apache 2.4.25-3):
PHP version (7.0):

The issue you are facing:

Client can’t sync a folder : get error “service unavailable”, can’t download the folder.
Even with the web app the folder can’t downloaded, received zip file does not contain downloaded folder but strange configuration file not related in any way on the source folder.

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

Steps to replicate it:

  1. Upload a folder with many file (± 4.7 gb)
  2. Try to sync this folder with nextcloud client (linux)-> fail “service unavailable”
  3. Try to donwload it from the web app -> get a folder with files not related with the initial folder, config files (docprops, _rels, word and content types file) .

The output of your Nextcloud log in Admin > Logging:

https://pastebin.com/HN1VbYfU

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

<?php
$CONFIG = array (
  'instanceid' => 'oc1j22tq1wal',
  'passwordsalt' => '<removed>',
  'secret' => '<removed>',
  'trusted_domains' => 
  array (
    0 => 'cloud.octarine.io',
  ),
  'datadirectory' => '/mnt/md127/nextcloud/data',
  'overwrite.cli.url' => '<removed>',
  'dbtype' => 'mysql',
  'version' => '13.0.6.1',
  'dbname' => '<removed>',
  'dbhost' => 'localhost',
  'dbtableprefix' => 'oc_',
  'dbuser' => '<removed>',
  'dbpassword' => '<removed>',
  'logtimezone' => 'UTC',
  'installed' => true,
  'mail_smtpmode' => 'php',
  'mail_from_address' => 'admin',
  'mail_domain' => '<removed>',
  'loglevel' => 2,
  'mail_smtphost' => '<removed>',
  'maintenance' => false,
  'appstore.experimental.enabled' => true,
  'theme' => '',
  'updatechecker' => false,
  'htaccess.RewriteBase' => '/',
  'memcache.local' => '\\OC\\Memcache\\APCu',
  'updater.release.channel' => 'stable',
  'data-fingerprint' => '<removed>',
);

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

94.224.19.209 - orso [19/Sep/2018:08:01:30 +0200] "PROPFIND /remote.php/dav/files/orso/ HTTP/1.1" 207 1334 "-" "Mozilla/5.0 (Windows) mirall/2.3.3 (build 1) (Nextcloud)"
94.224.19.209 - orso [19/Sep/2018:08:02:00 +0200] "PROPFIND /remote.php/dav/files/orso/ HTTP/1.1" 207 1334 "-" "Mozilla/5.0 (Windows) mirall/2.3.3 (build 1) (Nextcloud)"
94.224.19.209 - orso [19/Sep/2018:08:02:30 +0200] "PROPFIND /remote.php/dav/files/orso/ HTTP/1.1" 207 1334 "-" "Mozilla/5.0 (Windows) mirall/2.3.3 (build 1) (Nextcloud)"
94.224.19.209 - orso [19/Sep/2018:08:03:00 +0200] "PROPFIND /remote.php/dav/files/orso/ HTTP/1.1" 207 1334 "-" "Mozilla/5.0 (Windows) mirall/2.3.3 (build 1) (Nextcloud)"
94.224.19.209 - orso [19/Sep/2018:08:03:30 +0200] "PROPFIND /remote.php/dav/files/orso/ HTTP/1.1" 207 6115 "-" "Mozilla/5.0 (Windows) mirall/2.3.3 (build 1) (Nextcloud)"
94.224.19.209 - orso [19/Sep/2018:08:04:00 +0200] "PROPFIND /remote.php/dav/files/orso/ HTTP/1.1" 207 1334 "-" "Mozilla/5.0 (Windows) mirall/2.3.3 (build 1) (Nextcloud)"
<nothing really usefull...>
2

The issue was caused by a file located into that folder, removing the file (no longer needed) solved the problem.