我正在运行我的mysql数据库的基本备份。我不确定为什么它关闭了。 我正在收到备份已完成的消息，并且在准备后正在完成。 但实例仍然崩溃。 我正在运行两个实例，只备份一个实例。
xtrabackup --defaults-file=/etc/alternatives/my.cnf --defaults-group=mysqld5 --socket=/var/run/mysqld/db5.sock --user=mysqladmin --password=password --backup --throttle 400 --target-dir=/mysqlbackup/current --no-timestamp 2> /var/backup.log;
我 cat 日志文件以确保它已完成并且确实完成。然后我运行准备
xtrabackup --prepare --use-memory=5G --target-dir=/mysqlbackup/current 2 >> /var/backup.log;
我的日志文件有
xtrabackup: cd to /mysqlbackup/current
xtrabackup: This target seems to be not prepared yet.
Doing recovery: scanned up to log sequence number 5642017177088 (8%)
Doing recovery: scanned up to log sequence number 5642076559654 (99%)
Database was not shutdown normally
Starting crash recovery
Progress in percent: 0 1 2 ... 99
Apply batch completed
InnoDB: 96 redo rollback segment(s) found. 1 redo rollback segment(s) are active.
InnoDB: 32 non-redo rollback segment(s) are active.
InnoDB: page_cleaner: 1000ms intended loop took 748935ms. The settings might not be optimal. (flushed=0 and evicted=0, during the time.)
InnoDB: 5.7.26 started; log sequence number 5642076559654
xtrabackup: Last MySQL binlog file position 7017599, file name binlog.000009
xtrabackup: Recovered WSREP position: febfad99-09fe-11ea-ad83-57c73422d738:27384750
xtrabackup: starting shutdown with innodb_fast_shutdown = 1
InnoDB: FTS optimize thread exiting.
InnoDB: Starting shutdown...
InnoDB: Shutdown completed; log sequence number 5642076561674
InnoDB: Number of pools: 1
xtrabackup: innodb_data_home_dir = .
InnoDB: New log files created, LSN=5642076561674
InnoDB: Doing recovery: scanned up to log sequence number 5642076561941 (0%)
InnoDB: Database was not shutdown normally!
InnoDB: Starting crash recovery
InnoDB: Starting shutdown...
InnoDB: Shutdown completed; log sequence number 5642076561960
200213 08:05:36 completed OK!
连接到正在运行的MySQL服务器，并在客户端中运行以下命令：
mysql> SHOW STATUS LIKE 'Uptime';
+---------------+--------+
| Variable_name | Value |
+---------------+--------+
| Uptime | 268121 |
+---------------+--------+
该值是自MySQL服务器上次启动以来的秒数(我上面显示的示例来自我自己的笔记本电脑上的mysql，计算为74小时，这是我最后一次重新启动(。
我想你会发现你的正常运行时间值表明你的MySQL服务器在备份期间运行良好。
Percona XtraBackup不会重新启动您的MySQL服务器。它重新启动自己的InnoDB引擎，以针对刚刚备份的文件模拟崩溃恢复。
XtraBackup在MySQL本身中使用了大量从InnoDB引擎借来的代码，因此它保持了与InnoDB文件格式的兼容性。它使用InnoDB的崩溃恢复功能来"准备"其InnoDB文件的副本，以解决任何未完成的事务。
通过从InnoDB引擎借用代码，它会输出类似的消息。