将每个应更改的缓存相关系统变量设置为其新值。例如，将缓存超时时间从默认值（300 秒）更改为 600 秒：Set each cache-related system variable that should be changed to its new value. For example, change the cache timeout value from the default (300 seconds) to 600 seconds:

mysql> SET GLOBAL ssl_session_cache_timeout = 600;

由于重新配置过程的工作方式，每对系统变量和状态变量的成员可能会暂时具有不同的值。The members of each pair of system and status variables may have different values temporarily due to the way the reconfiguration procedure works.

mysql> SHOW VARIABLES LIKE 'ssl_session_cache_timeout';
+---------------------------+-------+
| Variable_name             | Value |
+---------------------------+-------+
| ssl_session_cache_timeout | 600   |
+---------------------------+-------+
1 row in set (0.00 sec)

mysql> SHOW STATUS LIKE 'Ssl_session_cache_timeout';
+---------------------------+-------+
| Variable_name             | Value |
+---------------------------+-------+
| Ssl_session_cache_timeout | 300   |
+---------------------------+-------+
1 row in set (0.00 sec)

有关设置变量值的更多信息，请参阅 系统变量赋值。For additional information about setting variable values, see System Variable Assignment.

执行 ALTER INSTANCE RELOAD TLS。该语句根据当前缓存相关系统变量的值重新配置活动的 TLS 上下文。同时，它还设置缓存相关状态变量以反映新的活动缓存值。该语句需要 CONNECTION_ADMIN 权限。Execute ALTER INSTANCE RELOAD TLS. This statement reconfigures the active TLS context from the current values of the cache-related system variables. It also sets the cache-related status variables to reflect the new active cache values. The statement requires the CONNECTION_ADMIN privilege.

mysql> ALTER INSTANCE RELOAD TLS;
Query OK, 0 rows affected (0.01 sec)
  
mysql> SHOW VARIABLES LIKE 'ssl_session_cache_timeout';
+---------------------------+-------+
| Variable_name             | Value |
+---------------------------+-------+
| ssl_session_cache_timeout | 600   |
+---------------------------+-------+
1 row in set (0.00 sec)

mysql> SHOW STATUS LIKE 'Ssl_session_cache_timeout';
+---------------------------+-------+
| Variable_name             | Value |
+---------------------------+-------+
| Ssl_session_cache_timeout | 600   |
+---------------------------+-------+
1 row in set (0.00 sec)

在执行 ALTER INSTANCE RELOAD TLS 后建立的新连接将使用新的 TLS 上下文。现有连接不受影响。New connections established after execution of ALTER INSTANCE RELOAD TLS use the new TLS context. Existing connections remain unaffected.

调用 mysql 来建立与运行 MySQL 8.4 服务器的加密连接。Invoke mysql to establish an encrypted connection to a server running MySQL 8.4.

使用 ssl_session_data_print 命令指定一个文件路径，在该文件中可以安全地存储当前活动的会话数据。例如：Use the ssl_session_data_print command to specify the path to a file where you can store the currently active session data securely. For example:

mysql> ssl_session_data_print ~/private-dir/session.txt

会话数据以空字符终止的 PEM 编码 ANSI 字符串形式获得。如果省略路径和文件名，字符串将打印到标准输出。Session data are obtained in the form of a null-terminated, PEM encoded ANSI string. If you omit the path and file name, the string prints to standard output.

从命令解释器的提示符中，调用任何 MySQL 客户端程序以建立到相同服务器的新加密连接。要重用会话数据，请指定 --ssl-session-data 命令行选项及文件参数。From the prompt of your command interpreter, invoke any MySQL client program to establish a new encrypted connection to the same server. To reuse the session data, specify the --ssl-session-data command-line option and the file argument.

例如，使用 mysql 建立新连接：For example, establish a new connection using mysql:

mysql -u admin -p --ssl-session-data=~/private-dir/session.txt

然后使用 mysqlshow 客户端：and then mysqlshow client:

mysqlshow -u admin -p --ssl-session-data=~/private-dir/session.txt
Enter password: *****
+--------------------+
|     Databases      |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
| world              |
+--------------------+

在每个示例中，客户端在建立与同一服务器的新连接时尝试恢复原始会话。In each example, the client attempts to resume the original session while it establishes a new connection to the same server.

要确认 mysql 是否重用了会话，请查看 status 命令的输出。如果当前活动的 mysql 连接确实恢复了会话，状态信息将包含 SSL session reused: true。To confirm whether mysql reused a session, see the output from the status command. If the currently active mysql connection did resume the session, the status information includes SSL session reused: true.