Can't access files after configuring Transactional file warning

I tried to solve the message that I get in admin page:

Transactional file locking should be configured to use memory-based locking, not the default slow database-based locking. See the documentation :arrow_upper_right: for more information.

And I installed Redis succesfully , running the command systemctl status redis

● redis.service - Redis In-Memory Data Store
   Loaded: loaded (/etc/systemd/system/redis.service; enabled; vendor preset: enabled)
   Active: active (running) since Tue 2017-10-31 07:30:20 UTC; 24min ago
 Main PID: 1053 (redis-server)
    Tasks: 4
   Memory: 2.5M
      CPU: 1.981s
   CGroup: /system.slice/redis.service
           └─1053 /usr/local/bin/redis-server 127.0.0.1:0

Oct 31 07:30:20 myserver redis-server[1053]:   `-._    `-._`-.__.-'_.-'    _.-'
Oct 31 07:30:20 myserver redis-server[1053]:  |`-._`-._    `-.__.-'    _.-'_.-'|
Oct 31 07:30:20 myserver redis-server[1053]:  |    `-._`-._        _.-'_.-'    |
Oct 31 07:30:20 myserver redis-server[1053]:   `-._    `-._`-.__.-'_.-'    _.-'
Oct 31 07:30:20 myserver redis-server[1053]:       `-._    `-.__.-'    _.-'
Oct 31 07:30:20 myserver redis-server[1053]:           `-._        _.-'
Oct 31 07:30:20 myserver redis-server[1053]:               `-.__.-'
Oct 31 07:30:20 myserver redis-server[1053]: 1053:M 31 Oct 07:30:20.784 # Server initialized
Oct 31 07:30:20 myserver redis-server[1053]: 1053:M 31 Oct 07:30:20.785 * DB loaded from disk: 0.001 seconds
Oct 31 07:30:20 myserver redis-server[1053]: 1053:M 31 Oct 07:30:20.785 * The server is now ready to accept connections at /tmp/redis.sock

The message is now gone, but I can't access the files now. When I try to open a file I get

ownCloud

Internal Server Error


Technical details

Remote Address: my-ip-address
Request ID: n1nqcTv5urc28gu41t0E
ownCloud – A safe home for all your data

If remove Redis configuration from the config.php I can access my files. Any hint why is this happening?

Server configuration

Operating system: Ubuntu 16.04

Web server: Apache2

Database: MySQL

PHP version: PHP Version 7.0.22-0ubuntu0.16.04.1

ownCloud version: 10.0.3.3

Updated from an older ownCloud or fresh install: fresh

Where did you install ownCloud from: owncloud

Signing status (ownCloud 9.0 and above): No errors have been found.

The content of config/config.php:

{
    "system": {
        "instanceid": "ocvgzukzb4qp",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "my.domain.com"
        ],
        "datadirectory": "\/var\/www\/html\/my.domain.com\/owncloud\/data",
        "overwrite.cli.url": "http:\/\/myfolder\/owncloud",
        "dbtype": "mysql",
        "version": "10.0.3.3",
        "dbname": "myownclouddb",
        "dbhost": "localhost",
        "dbtableprefix": "oc_",
        "mysql.utf8mb4": true,
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "logtimezone": "UTC",
        "installed": true,
        "mail_from_address": "mycloud",
        "mail_smtpmode": "php",
        "mail_domain": "mydomain.com",
        'filelocking.enabled' => true,
         'memcache.locking' => '\\OC\\Memcache\\Redis',
         'redis' =>
                 array (
                           'host' => '/var/run/redis/redis.sock',
                            'port' => 0,
                            'timeout' => 0.0,
                          ),
          'loglevel' => 2,
      }
}

List of activated apps: Announcements

Are you using external storage, if yes which one: no

Are you using encryption: yes

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

Client configuration

Browser: Chrome

Operating system: Windows 10

Logs

ownCloud log (data/owncloud.log)

{"reqId":"n1nqcTv5urc28gu41t0E","level":4,"time":"2017-10-31T07:48:52+00:00","remoteAddr":"my.ip.address.here","user":"myusername","app":"webdav","method":"GET","url":"\/mycloud\/remote.php\/webdav\/ownCloud%20Manual.pdf","message":"Exception: {\"Message\":\"Redis server went away\",\"Exception\":\"RedisException\",\"Code\":0,\"Trace\":\"#0 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/private\\\/Memcache\\\/Redis.php(111): Redis->incrBy('1466e1df2bfd800...', 1)\\n#1 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/private\\\/Lock\\\/MemcacheLockingProvider.php(76): OC\\\\Memcache\\\\Redis->inc('files\\\/ce83f8e45...')\\n#2 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/private\\\/Files\\\/Storage\\\/Common.php(653): OC\\\\Lock\\\\MemcacheLockingProvider->acquireLock('files\\\/ce83f8e45...', 1)\\n#3 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/private\\\/Files\\\/Storage\\\/Wrapper\\\/Wrapper.php(589): OC\\\\Files\\\\Storage\\\\Common->acquireLock('files\\\/ownCloud ...', 1, Object(OC\\\\Lock\\\\MemcacheLockingProvider))\\n#4 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/private\\\/Files\\\/Storage\\\/Wrapper\\\/Wrapper.php(589): OC\\\\Files\\\\Storage\\\\Wrapper\\\\Wrapper->acquireLock('files\\\/ownCloud ...', 1, Object(OC\\\\Lock\\\\MemcacheLockingProvider))\\n#5 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/private\\\/Files\\\/Storage\\\/Wrapper\\\/Wrapper.php(589): OC\\\\Files\\\\Storage\\\\Wrapper\\\\Wrapper->acquireLock('files\\\/ownCloud ...', 1, Object(OC\\\\Lock\\\\MemcacheLockingProvider))\\n#6 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/private\\\/Files\\\/Storage\\\/Wrapper\\\/Wrapper.php(589): OC\\\\Files\\\\Storage\\\\Wrapper\\\\Wrapper->acquireLock('files\\\/ownCloud ...', 1, Object(OC\\\\Lock\\\\MemcacheLockingProvider))\\n#7 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/private\\\/Files\\\/View.php(1904): OC\\\\Files\\\\Storage\\\\Wrapper\\\\Wrapper->acquireLock('files\\\/ownCloud ...', 1, Object(OC\\\\Lock\\\\MemcacheLockingProvider))\\n#8 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/private\\\/Files\\\/View.php(2007): OC\\\\Files\\\\View->lockPath('\\\/ownCloud Manua...', 1, false)\\n#9 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/private\\\/Files\\\/View.php(1109): OC\\\\Files\\\\View->lockFile('\\\/ownCloud Manua...', 1)\\n#10 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/private\\\/Files\\\/View.php(966): OC\\\\Files\\\\View->basicOperation('fopen', '\\\/ownCloud Manua...', Array, 'rb')\\n#11 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/apps\\\/dav\\\/lib\\\/Connector\\\/Sabre\\\/File.php(337): OC\\\\Files\\\\View->fopen('ownCloud Manual...', 'rb')\\n#12 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/composer\\\/sabre\\\/dav\\\/lib\\\/DAV\\\/CorePlugin.php(85): OCA\\\\DAV\\\\Connector\\\\Sabre\\\\File->get()\\n#13 [internal function]: Sabre\\\\DAV\\\\CorePlugin->httpGet(Object(Sabre\\\\HTTP\\\\Request), Object(Sabre\\\\HTTP\\\\Response))\\n#14 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/composer\\\/sabre\\\/event\\\/lib\\\/EventEmitterTrait.php(105): call_user_func_array(Array, Array)\\n#15 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/composer\\\/sabre\\\/dav\\\/lib\\\/DAV\\\/Server.php(479): Sabre\\\\Event\\\\EventEmitter->emit('method:GET', Array)\\n#16 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/composer\\\/sabre\\\/dav\\\/lib\\\/DAV\\\/Server.php(254): Sabre\\\\DAV\\\\Server->invokeMethod(Object(Sabre\\\\HTTP\\\\Request), Object(Sabre\\\\HTTP\\\\Response))\\n#17 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/apps\\\/dav\\\/appinfo\\\/v1\\\/webdav.php(63): Sabre\\\\DAV\\\\Server->exec()\\n#18 \\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/remote.php(165): require_once('\\\/var\\\/www\\\/html\\\/s...')\\n#19 {main}\",\"File\":\"\\\/var\\\/www\\\/html\\\/my.domain.com\\\/mycloud\\\/lib\\\/private\\\/Memcache\\\/Redis.php\",\"Line\":111,\"User\":\"myusername\"}"}

Browser log (When I try to open a file I get a page with this message:)

ownCloud

Internal Server Error


Technical details

Remote Address: my-ip-address
Request ID: n1nqcTv5urc28gu41t0E
ownCloud – A safe home for all your data

To me it looks like this:

doesn't fit together with this:

It worked..
So obvious, but I missed it..

Thanks a lot!