我使用的是symfony4，mysql版本是8.0.11，使用的是用户而不是根用户登录，当我尝试使用这个命令时 php bin/console make:migration 我得到这个错误：
In AbstractMySQLDriver.php line 126:
An exception occurred in driver: SQLSTATE[HY000] [2006] MySQL server has gone away
In PDOConnection.php line 50:
SQLSTATE[HY000] [2006] MySQL server has gone away
In PDOConnection.php line 46:
SQLSTATE[HY000] [2006] MySQL server has gone away
In PDOConnection.php line 46:
PDO::__construct(): Unexpected server respose while doing caching_sha2 auth: 109然后我尝试在网上搜索，发现mysql变量出了问题 wait_timeout 以及 max_allowed_packet 必须更改文件中的变量 /etc/mysql/my.cnf ，问题是当我去编辑该文件时，我只发现：
# Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License, version 2.0,
# as published by the Free Software Foundation.
#
# This program is also distributed with certain software (including
# but not limited to OpenSSL) that is licensed under separate terms,
# as designated in a particular file or component or in included license
# documentation. The authors of MySQL hereby grant you an additional
# permission to link the program and your derivative works with the
# separately licensed software that they have included with MySQL.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License, version 2.0, for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
#
# The MySQL Server configuration file.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html
# * IMPORTANT: Additional settings that can override those from this file!
# The files must end with '.cnf', otherwise they'll be ignored.
!includedir /etc/mysql/conf.d/
!includedir /etc/mysql/mysql.conf.d/因此，我试图看到一个名为“why is/etc/mysql/my.cnf empty？”的线程，一个用户说使用以下路径之一：
/etc/mysql/conf.d/
/etc/mysql/mysql.conf.d/
/etc/mysql/mysql.conf.d/mysqld.cnf所以我试着。。。 /etc/mysql/conf.d/ :
## Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License, version 2.0,
# as published by the Free Software Foundation.
#
# This program is also distributed with certain software (including
# but not limited to OpenSSL) that is licensed under separate terms,
# as designated in a particular file or component or in included license
# documentation. The authors of MySQL hereby grant you an additional
# permission to link the program and your derivative works with the
# separately licensed software that they have included with MySQL.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License, version 2.0, for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
#
# The MySQL Client configuration file.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html
[mysql]在文件中 /etc/mysql/mysql.conf.d/ :
# Copyright (c) 2014, 2017, Oracle and/or its affiliates. All rights reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License, version 2.0,
# as published by the Free Software Foundation.
#
# This program is also distributed with certain software (including
# but not limited to OpenSSL) that is licensed under separate terms,
# as designated in a particular file or component or in included license
# documentation. The authors of MySQL hereby grant you an additional
# permission to link the program and your derivative works with the
# separately licensed software that they have included with MySQL.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License, version 2.0, for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
#
# The MySQL Server configuration file.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html
[mysqld]
pid-file = /var/run/mysqld/mysqld.pid
socket = /var/run/mysqld/mysqld.sock
datadir = /var/lib/mysql
log-error = /var/log/mysql/error.log在文件里呢 /etc/mysql/mysql.conf.d/mysqld.cnf :
# Copyright (c) 2014, 2017, Oracle and/or its affiliates. All rights reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License, version 2.0,
# as published by the Free Software Foundation.
#
# This program is also distributed with certain software (including
# but not limited to OpenSSL) that is licensed under separate terms,
# as designated in a particular file or component or in included license
# documentation. The authors of MySQL hereby grant you an additional
# permission to link the program and your derivative works with the
# separately licensed software that they have included with MySQL.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License, version 2.0, for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
#
# The MySQL Server configuration file.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html
[mysqld]
pid-file = /var/run/mysqld/mysqld.pid
socket = /var/run/mysqld/mysqld.sock
datadir = /var/lib/mysql
log-error = /var/log/mysql/error.log在这些文件中，我没有找到mysql变量 wait_timeout 以及 max_allowed_packet ，因此，如果有人能帮我解决这个问题，请提前感谢。：）
p、 s：（我已经运行了这个命令 php bin/console make:migration 在这个错误发生之前有好几次，还创建了数据库并运行良好，所以它似乎不是安装问题）。
更新：似乎成功地改变了这两个变量 wait_timeout 以及 max_allowed_packet 通过在三个文件中添加以下内容
max_allowed_packet=1024M
wait_timeout=3000000然后使用这个命令 sudo service mysql restart 给我这个：
mysql> SHOW global VARIABLES LIKE "wait_timeout";
+---------------+---------+
| Variable_name | Value |
+---------------+---------+
| wait_timeout | 3000000 |
+---------------+---------+
1 row in set (0,00 sec)
mysql> SHOW VARIABLES like 'max_allowed_packet';
+--------------------+------------+
| Variable_name | Value |
+--------------------+------------+
| max_allowed_packet | 1073741824 |
+--------------------+------------+
1 row in set (0,00 sec)但当我尝试使用这个命令时 php bin/console make:migration 它给了我同样的错误，上面提到过这个帖子，也试着改了 wait_timeout 用同样的方法将变量设置为300，得到了同样的结果：(
使用此命令 sudo vim /var/log/mysql/error.log 我明白了：
2018-07-29T18:55:18.382164Z 0 [Warning] [MY-010909] [Server] /usr/sbin/mysqld: Forcing close of thread 8 user: 'alexandre'.
2018-07-29T18:55:20.288756Z 0 [System] [MY-010910] [Server] /usr/sbin/mysqld: Shutdown complete (mysqld 8.0.11) MySQL Community Server - GPL.
2018-07-29T18:55:20.642118Z 0 [System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.11) starting as process 31833
2018-07-29T18:55:21.704556Z 0 [Warning] [MY-010068] [Server] CA certificate ca.pem is self signed.
2018-07-29T18:55:21.720385Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.11' socket: '/var/run/mysqld/mysqld.sock' port: 3306 MySQL Community Server - GPL.更新：我已经设计了mysql和php，改成了MySQL5.7和PHP7.2.7，php的变化可能已经解决了这个问题，根据用户@jibe的链接，如果还有人不能解决这个问题，我就让另外两个链接链接1和链接2。
问题用户更新：一个名为@ganesh的用户也给出了这个解决方案：alter user username @ localhost 通过“password”标识为缓存_sha2_密码；
或
ALTER USER 'username'@'localhost' IDENTIFIED WITH mysql_native_password BY 'password';希望对你有帮助：d
1条答案
按热度按时间cbeh67ev1#
在mysql配置文件（centos，etc/my.conf）中添加以下行：
这就成功了。希望有帮助。
我的环境：
centos 7号
PHP7.2
mysql 8版