Doctrine\\DBAL\\Driver\\PDOException SQLSTATE[HY000] [2006] MySQL 服务器已经消失

Question

I have a Laravel 6.2 application and so far it is a basic application almost out of the box. I used Laravels out of the box auth scaffolding and created a user and am able to see this user in my db (mysql workbench). The user is created but then I use the php artisan serve command then try to sign in as the user I just created the browser hangs for about 1 minute then spits out the following error:

Doctrine\DBAL\Driver\PDOException
SQLSTATE[HY000] [2006] MySQL server has gone away

I have researched other posts relating to this command and checked my mysql timeout and I increased the limits and it still outputs this error. What could be the issue? I am including output from mysql so you can all see.

SHOW VARIABLES LIKE '%timeout%'; 
+-----------------------------------+----------+
| Variable_name                     | Value    |
+-----------------------------------+----------+
| connect_timeout                   | 10       |
| delayed_insert_timeout            | 300      |
| have_statement_timeout            | YES      |
| innodb_flush_log_at_timeout       | 1        |
| innodb_lock_wait_timeout          | 50       |
| innodb_rollback_on_timeout        | OFF      |
| interactive_timeout               | 31536000 |
| lock_wait_timeout                 | 31536000 |
| mysqlx_connect_timeout            | 30       |
| mysqlx_idle_worker_thread_timeout | 60       |
| mysqlx_interactive_timeout        | 28800    |
| mysqlx_port_open_timeout          | 0        |
| mysqlx_read_timeout               | 30       |
| mysqlx_wait_timeout               | 28800    |
| mysqlx_write_timeout              | 60       |
| net_read_timeout                  | 30       |
| net_write_timeout                 | 60       |
| rpl_stop_slave_timeout            | 31536000 |
| slave_net_timeout                 | 60       |
| wait_timeout                      | 31536000 |
+-----------------------------------+----------+

SHOW STATUS WHERE variable_name = 'Threads_connected';
+-------------------+-------+
| Variable_name     | Value |
+-------------------+-------+
| Threads_connected | 2     |
+-------------------+-------+

SHOW STATUS WHERE variable_name LIKE 'Connections';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| Connections   | 24    |
+---------------+-------+

Mysql Version

mysql --version
mysql  Ver 8.0.18-0ubuntu0.19.10.1 for Linux on x86_64 ((Ubuntu))

PING 127.0.0.1 (127.0.0.1) 56(84) bytes of data.
64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.052 ms
64 bytes from 127.0.0.1: icmp_seq=2 ttl=64 time=0.058 ms
64 bytes from 127.0.0.1: icmp_seq=3 ttl=64 time=0.060 ms
64 bytes from 127.0.0.1: icmp_seq=4 ttl=64 time=0.058 ms

Answer 1

The php.net manual has an explanation:

When running a PHP version before 7.1.16, or PHP 7.2 before 7.2.4, set MySQL 8 Server's default password plugin to mysql_native_password or else you will see errors similar to The server requested authentication method unknown to the client [caching_sha2_password] even when caching_sha2_password is not used.

This is because MySQL 8 defaults to caching_sha2_password, a plugin that is not recognized by the older PHP (mysqlnd) releases. Instead, change it by setting default_authentication_plugin=mysql_native_password in my.cnf. The caching_sha2_password plugin will be supported in a future PHP release. In the meantime, the mysql_xdevapi extension does support it.

Source