Eu tenho usado o MySQL com um local diferente para a data do banco de dados desde o Ubuntu 12.04 e não tive problemas. Minha configuração foi assim:
sudo ln -s /home/db/mysql /var/lib/mysql
/home/db/** rwk, a /etc/apparmor.d/usr.sbin.mysqld
Funcionou muito bem até o Ubuntu 14.04. Eu tenho lutado o dia todo, mas parece que não consigo fazer funcionar.
Parece que o AppArmor não está dando permissões solicitadas ao MySQL na pasta / home / db, já que se eu usar chmod 777 -R /home/db , ele funciona.
Caso contrário, eu entendo isso:
$ sudo service mysql start
start: Job failed to start
E o log:
140420 22:42:56 [Warning] Using unique option prefix myisam-recover instead of myisam-recover-options is deprecated and will be removed in a future release. Please use the full name instead.
140420 22:42:56 [Note] Plugin 'FEDERATED' is disabled.
/usr/sbin/mysqld: Can't find file: './mysql/plugin.frm' (errno: 13)
140420 22:42:56 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
140420 22:42:56 InnoDB: The InnoDB memory heap is disabled
140420 22:42:56 InnoDB: Mutexes and rw_locks use GCC atomic builtins
140420 22:42:56 InnoDB: Compressed tables use zlib 1.2.8
140420 22:42:56 InnoDB: Using Linux native AIO
140420 22:42:56 InnoDB: Initializing buffer pool, size = 128.0M
140420 22:42:56 InnoDB: Completed initialization of buffer pool
140420 22:42:56 InnoDB: highest supported file format is Barracuda.
140420 22:42:57 InnoDB: Waiting for the background threads to start
140420 22:42:58 InnoDB: 5.5.35 started; log sequence number 242217316
140420 22:42:58 [Note] Server hostname (bind-address): '127.0.0.1'; port: 3306
140420 22:42:58 [Note] - '127.0.0.1' resolves to '127.0.0.1';
140420 22:42:58 [Note] Server socket created on IP: '127.0.0.1'.
140420 22:42:58 [ERROR] /usr/sbin/mysqld: Can't find file: './mysql/host.frm' (errno: 13)
140420 22:42:58 [ERROR] Fatal error: Can't open and lock privilege tables: Can't find file: './mysql/host.frm' (errno: 13)
140420 22:42:58 [Warning] Using unique option prefix myisam-recover instead of myisam-recover-options is deprecated and will be removed in a future release. Please use the full name instead.
140420 22:42:58 [Note] Plugin 'FEDERATED' is disabled.
/usr/sbin/mysqld: Can't find file: './mysql/plugin.frm' (errno: 13)
140420 22:42:58 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
140420 22:42:58 InnoDB: The InnoDB memory heap is disabled
140420 22:42:58 InnoDB: Mutexes and rw_locks use GCC atomic builtins
140420 22:42:58 InnoDB: Compressed tables use zlib 1.2.8
140420 22:42:58 InnoDB: Using Linux native AIO
140420 22:42:58 InnoDB: Initializing buffer pool, size = 128.0M
140420 22:42:58 InnoDB: Completed initialization of buffer pool
140420 22:42:59 InnoDB: highest supported file format is Barracuda.
140420 22:42:59 InnoDB: Waiting for the background threads to start
140420 22:43:00 InnoDB: 5.5.35 started; log sequence number 242217316
140420 22:43:00 [Note] Server hostname (bind-address): '127.0.0.1'; port: 3306
140420 22:43:00 [Note] - '127.0.0.1' resolves to '127.0.0.1';
140420 22:43:00 [Note] Server socket created on IP: '127.0.0.1'.
140420 22:43:00 [ERROR] /usr/sbin/mysqld: Can't find file: './mysql/host.frm' (errno: 13)
140420 22:43:00 [ERROR] Fatal error: Can't open and lock privilege tables: Can't find file: './mysql/host.frm' (errno: 13)
140420 22:43:01 [Warning] Using unique option prefix myisam-recover instead of myisam-recover-options is deprecated and will be removed in a future release. Please use the full name instead.
140420 22:43:01 [Note] Plugin 'FEDERATED' is disabled.
/usr/sbin/mysqld: Can't find file: './mysql/plugin.frm' (errno: 13)
140420 22:43:01 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
140420 22:43:01 InnoDB: The InnoDB memory heap is disabled
140420 22:43:01 InnoDB: Mutexes and rw_locks use GCC atomic builtins
140420 22:43:01 InnoDB: Compressed tables use zlib 1.2.8
140420 22:43:01 InnoDB: Using Linux native AIO
140420 22:43:01 InnoDB: Initializing buffer pool, size = 128.0M
140420 22:43:01 InnoDB: Completed initialization of buffer pool
140420 22:43:01 InnoDB: highest supported file format is Barracuda.
140420 22:43:01 InnoDB: Waiting for the background threads to start
140420 22:43:02 InnoDB: 5.5.35 started; log sequence number 242217316
140420 22:43:02 [Note] Server hostname (bind-address): '127.0.0.1'; port: 3306
140420 22:43:02 [Note] - '127.0.0.1' resolves to '127.0.0.1';
140420 22:43:02 [Note] Server socket created on IP: '127.0.0.1'.
140420 22:43:02 [ERROR] /usr/sbin/mysqld: Can't find file: './mysql/host.frm' (errno: 13)
140420 22:43:02 [ERROR] Fatal error: Can't open and lock privilege tables: Can't find file: './mysql/host.frm' (errno: 13)
Este é um problema de permissões e não um problema do Apparmor.
O Apparmor funciona em conjunto com as permissões do DAC.
AppArmor provides an additional permission check to DAC. DAC is always checked in addition to the AppArmor permission checks. As such, AppArmor cannot override DAC to provide more access than what would be normally allowed.
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Tags permissions 14.04 mysql apparmor