After update my running typo3 v10 via composer (from v10.x to 10.y), I get a white site and when I switch to the Install-Tool (I can see it and login there), I get the following message:
Fatal error: Uncaught Error: Undefined constant 'MYSQLI_SERVER_PUBLIC_KEY' in /cms/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/Mysqli/MysqliConnection.php:252 Stack trace: #0 /cms/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/Mysqli/MysqliConnection.php(75): Doctrine\DBAL\Driver\Mysqli\MysqliConnection->setDriverOptions(Array) #1 /cms/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/Mysqli/Driver.php(16): Doctrine\DBAL\Driver\Mysqli\MysqliConnection->__construct(Array, 'xyz', 'zyx', Array) #2 /cms/vendor/doctrine/dbal/lib/Doctrine/DBAL/Connection.php(362): Doctrine\DBAL\Driver\Mysqli\Driver->connect(Array, 'xyz', 'zyx', Array) #3 /cms/public/typo3/sysext/core/Classes/Database/Connection.php(98): Doctrine\DBAL\Connection->connect() #4 /cms/vendor/doctrine/dbal/lib/Doctrine/DBAL/Connection.p in /cms/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/Mysqli/MysqliConnection.php on line 252
Server is from Strato.
Any idea, what's going wrong?
I got the answer from Peter in https://www.typo3.net/forum/thematik/zeige/thema/128385/ for this failure:
Paraphrasing from German:
Changing in "LocalConfiguration.php" the DB-Driver from "mysqli" into "pdo_mysql" and everything works fine. :-)