我正在从 MySQL 5.1 升级到 5.5，运行mysql_upgrade并获取以下输出：
# mysql_upgrade
Looking for 'mysql' as: mysql
Looking for 'mysqlcheck' as: mysqlcheck
FATAL ERROR: Upgrade failed
关于在哪里寻找正在发生的事情（或者没有发生的事情？）有什么想法，以便我可以修复所有错误并实际运行mysql_upgrade？
谢谢！
更多输出：
# mysql_upgrade --verbose
Looking for 'mysql' as: mysql
Looking for 'mysqlcheck' as: mysqlcheck
FATAL ERROR: Upgrade failed
# mysql_upgrade --debug-check --debug-info
Looking for 'mysql' as: mysql
Looking for 'mysqlcheck' as: mysqlcheck
FATAL ERROR: Upgrade failed
# mysql_upgrade --debug-info
Looking for 'mysql' as: mysql
Looking for 'mysqlcheck' as: mysqlcheck
FATAL ERROR: Upgrade failed
User time 0.00, System time 0.00
Maximum resident set size 1260, Integral resident set size 0
Non-physical pagefaults 447, Physical pagefaults 0, Swaps 0
Blocks in 0 out 16, Messages in 0 out 0, Signals 0
Voluntary context switches 9, Involuntary context switches 5
# mysql_upgrade --debug-check
Looking for 'mysql' as: mysql
Looking for 'mysqlcheck' as: mysqlcheck
FATAL ERROR: Upgrade failed
mysqld --skip-grant-tables通过关闭mysqladmin shutdown并通过 重新启动 mysql 后service mysql start，错误日志会反复循环显示以下一组错误：
130730 21:03:27 [Note] Plugin 'FEDERATED' is disabled.
/usr/sbin/mysqld: Table 'mysql.plugin' doesn't exist
130730 21:03:27 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
130730 21:03:27 InnoDB: The InnoDB memory heap is disabled
130730 21:03:27 InnoDB: Mutexes and rw_locks use GCC atomic builtins
130730 21:03:27 InnoDB: Compressed tables use zlib 1.2.3.4
130730 21:03:27 InnoDB: Initializing buffer pool, size = 20.0G
130730 21:03:29 InnoDB: Completed initialization of buffer pool
130730 21:03:30 InnoDB: highest supported file format is Barracuda.
InnoDB: Log scan progressed past the checkpoint lsn 588190222435
130730 21:03:30 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: Doing recovery: scanned up to log sequence number 588192055067
130730 21:03:30 InnoDB: Starting an apply batch of log records to the database...
InnoDB: Progress in percents: 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99
InnoDB: Apply batch completed
InnoDB: Last MySQL binlog file position 0 81298895, file name /var/log/mysql/mysql-bin.006008
130730 21:03:33 InnoDB: Waiting for the background threads to start
130730 21:03:34 InnoDB: 5.5.32 started; log sequence number 588192055067
130730 21:03:34 [Note] Recovering after a crash using /var/log/mysql/mysql-bin
130730 21:03:34 [Note] Starting crash recovery...
130730 21:03:34 [Note] Crash recovery finished.
130730 21:03:34 [Note] Server hostname (bind-address): '0.0.0.0'; port: 3306
130730 21:03:34 [Note] - '0.0.0.0' resolves to '0.0.0.0';
130730 21:03:34 [Note] Server socket created on IP: '0.0.0.0'.
130730 21:03:34 [ERROR] Fatal error: Can't open and lock privilege tables: Table 'mysql.host' doesn't exist
MySQL 启动时通过mysqld_safe --skip-grant-tables
130730 21:19:36 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql
130730 21:19:36 [Note] Plugin 'FEDERATED' is disabled.
130730 21:19:36 InnoDB: The InnoDB memory heap is disabled
130730 21:19:36 InnoDB: Mutexes and rw_locks use GCC atomic builtins
130730 21:19:36 InnoDB: Compressed tables use zlib 1.2.3.4
130730 21:19:37 InnoDB: Initializing buffer pool, size = 20.0G
130730 21:19:39 InnoDB: Completed initialization of buffer pool
130730 21:19:39 InnoDB: highest supported file format is Barracuda.
130730 21:19:42 InnoDB: Warning: allocated tablespace 566, old maximum was 0
130730 21:19:42 InnoDB: Waiting for the background threads to start
130730 21:19:43 InnoDB: 5.5.32 started; log sequence number 588192055067
130730 21:19:43 [Note] Server hostname (bind-address): '0.0.0.0'; port: 3306
130730 21:19:43 [Note] - '0.0.0.0' resolves to '0.0.0.0';
130730 21:19:43 [Note] Server socket created on IP: '0.0.0.0'.
130730 21:19:43 [Warning] Can't open and lock time zone table: Table 'mysql.time_zone_leap_second' doesn't exist trying to live without them
130730 21:19:43 [ERROR] Can't open and lock privilege tables: Table 'mysql.servers' doesn't exist
130730 21:19:43 [ERROR] Native table 'performance_schema'.'events_waits_current' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'events_waits_history' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'events_waits_history_long' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'setup_consumers' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'setup_instruments' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'setup_timers' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'performance_timers' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'threads' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'events_waits_summary_by_thread_by_event_name' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'events_waits_summary_by_instance' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'events_waits_summary_global_by_event_name' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'file_summary_by_event_name' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'file_summary_by_instance' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'mutex_instances' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'rwlock_instances' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'cond_instances' has the wrong structure
130730 21:19:43 [ERROR] Native table 'performance_schema'.'file_instances' has the wrong structure
130730 21:19:43 [Note] /usr/sbin/mysqld: ready for connections.
Version: '5.5.32-0ubuntu0.12.04.1-log' socket: '/var/run/mysqld/mysqld.sock' port: 3306 (Ubuntu)
据我了解，所有表结构/存在问题（与 mysql 系统表相关）都应通过运行以下命令进行纠正mysql_upgrade：
答案1
我认为它需要用户名和密码
mysql_upgrade -u root -p
如果我没有通过，我会得到你的错误
编辑：感谢大家的评论，现在我知道还有其他原因，也许不太常见，但最好也意识到它们
因此当你
- 你没有输入用户名和密码
- 你通过了你的认证，但他们错了
- MySQL 服务器未运行
- 权限表被破坏（然后你必须使用 重新启动 MySQL
mysqld --skip-grant-table） - 缺少表 mysql.plugin（启动 MySQL 时，您会看到有关该问题的错误，提示您运行...mysql_upgrade，但运行失败。您的 my.cnf 中可能有一些过时的配置）
答案2
我刚刚从 5.5 升级到 5.6 时遇到了这些精确的症状，结果发现这是一个服务可达性问题。
尽管 cli MySQL 客户端仅通过提供 -u 和 -p 即可连接到我的本地数据库实例，但我还需要为 mysql_upgrade 指定 -h 127.0.0.1，因为它正在尝试建立套接字文件连接，但尝试失败了。
答案3
这看起来像是一个 Plesk 服务器，使用 Plesk 时 Mysql 没有 root 权限，但 Mysql 的管理员名为 admin，因此这个命令应该可以在 Plesk 上运行，我之前尝试过：
mysql_upgrade -uadmin -p`cat /etc/psa/.psa.shadow`
答案4
同样的问题！我的解决方案来自http://www.freebsd.org/cgi/query-pr.cgi?pr=180624
简而言之：错误具有误导性！mysql_upgrade -u root -p在线运行数据库并提供 root 密码。