前のエントリで書いた通り、突然サーバーが高負荷になって何も受け付けなくなったので、仕方なくシャットダウン。再起動後にログを見回ったら、MySQL (実体はMariaDB) のログにエラーが記録されていた。やばい予感。
mysqld_safe Number of processes running now: 0 mysqld_safe mysqld restarted mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql [Note] /usr/libexec/mysqld (mysqld 5.5.44-MariaDB) starting as process 1532 ... InnoDB: The InnoDB memory heap is disabled InnoDB: Mutexes and rw_locks use GCC atomic builtins InnoDB: Compressed tables use zlib 1.2.7 InnoDB: Using Linux native AIO InnoDB: Initializing buffer pool, size = 128.0M InnoDB: Completed initialization of buffer pool InnoDB: highest supported file format is Barracuda. InnoDB: The log sequence number in ibdata files does not match InnoDB: the log sequence number in the ib_logfiles! InnoDB: Database was not shut down normally! InnoDB: Starting crash recovery. InnoDB: Reading tablespace information from the .ibd files... InnoDB: Restoring possible half-written data pages from the doublewrite InnoDB: buffer... InnoDB: Waiting for the background threads to start Percona XtraDB (http://www.percona.com) 5.5.43-MariaDB-37.2 started; log sequence number 13888240 [Note] Plugin 'FEEDBACK' is disabled. [Note] Server socket created on IP: '0.0.0.0'. [ERROR] mysqld: Table './mysql/user' is marked as crashed and should be repaired [Warning] Checking table: './mysql/user' [ERROR] mysql.user: 1 client is using or hasn't closed the table properly [ERROR] mysqld: Table './mysql/db' is marked as crashed and should be repaired [Warning] Checking table: './mysql/db' [ERROR] mysql.db: 1 client is using or hasn't closed the table properly [Note] Event Scheduler: Loaded 0 events [Note] /usr/libexec/mysqld: ready for connections. Version: '5.5.44-MariaDB' socket: '/var/lib/mysql/mysql.sock' port: 3306 MariaDB Server [ERROR] mysqld: Table './db1/wp_options' is marked as crashed and should be repaired [Warning] Checking table: './db1/wp_options' [ERROR] mysqld: Table './db1/wp_posts' is marked as crashed and should be repaired [Warning] Checking table: './db1/wp_posts' [ERROR] mysqld: Table './db1/wp_comments' is marked as crashed and should be repaired
WordPressは問題なく動作しているように見えるけど、念のためリカバリしておいたほうがいいだろう。ということで、エラーチェックとリカバリ用のコマンド (SQL) を覚え書き。
check table <table_name>; repair table <table_name>;
これらコマンドを実行してみたけど何も起きなかった。起動時に走ったリカバリ処理が問題を解決してくれた模様。大事にならなくて良かったねー
参考サイト
MySQL の壊れたテーブルを修復
http://macperson.net/mysql-table-repair/