See if nero’s thing worked. Otherwise, I am rather clueless - the redis port as “0”, is that correct?
Hmmm, looking at my own redis config, yes:
array (
'host' => '/var/run/redis/redis.sock',
'port' => 0,
'timeout' => 0,
'password' => '',
'dbindex' => 0,
),
but you can try those settings.
Redis gives no other error messages? This all seems quite boring and correct… The error in the Nextcloud log seems to claim there’s no file, as in, no thumbnails? You could use the thumbnail generator app to create them? See apps.nextcloud.com
Sorry, this isn’t my expertise either…