Hello,
i reinstalled the whole system today. The nextcloud install was also done correctly … i could log in and use nextcloud without issues after the install. But after a restart from ubuntu (the server), it was not possible to access nextcloud anymore. I always get a blank/white page after typing in the IP. At the bottom you can see the error log.
I used this tutorial to install it: https://www.youtube.com/watch?v=nXr_muYB6xI
Nextcloud version: 12
Operating system and version: 16.04 LTS
Apache version: 2.4.18
PHP version: 7.0.22
Error log apache2:
[Mon Oct 23 15:07:22.998751 2017] [:error] [pid 1344] [client 100.92.220.12:54855] PHP Fatal error: Uncaught Doctrine\DBAL\DBALException: Failed to connect to the database: An exception occured in driver: SQLSTATE[HY000] [2002] No such file or directory in /var/www/html/nextcloud/lib/private/DB/Connection.php:61\nStack trace:\n#0 /var/www/html/nextcloud/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/Connection.php(429): OC\DB\Connection->connect()\n#1 /var/www/html/nextcloud/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/Connection.php(389): Doctrine\DBAL\Connection->getDatabasePlatformVersion()\n#2 /var/www/html/nextcloud/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/Connection.php(328): Doctrine\DBAL\Connection->detectDatabasePlatform()\n#3 /var/www/html/nextcloud/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/Connection.php(623): Doctrine\DBAL\Connection->getDatabasePlatform()\n#4 /var/www/html/nextcloud/lib/private/DB/Connection.php(148): Doctrine\DBAL\Connection->setTransactionIsolation(2)\n#5 /var/www/html/nextcloud/3rdparty/doctrine/dbal/lib/Doctrine/DBAL/DriverManager.php(172): OC\DB\Connection->__construct(Array, Object(Doctrin in /var/www/html/nextcloud/lib/private/DB/Connection.php on line 61