MySQL Bugs: #71667: Unit tests not able to start the MySQL instance to run the tests

Bug #71667	Unit tests not able to start the MySQL instance to run the tests
Submitted:	11 Feb 2014 10:34	Modified:	28 Mar 2014 16:58
Reporter:	Peeyush Gupta	Email Updates:
Status:	Closed	Impact on me:	None
Category:	Connector / Python	Severity:	S3 (Non-critical)
Version:	1.1.4	OS:	Any
Assigned to:		CPU Architecture:	Any

Description:
The test suite is not able to start the MySQL Server instance to run the
tests.

PYTHONPATH=build/lib.linux-x86_64-2.7/ python unittests.py
--with-mysql=/usr/ --mysql-topdir=./mysql_myconnpy/ --verbosity=10
--bind-address=:: --host=::1

$ cat mysql_myconnpy/cpy_server1/bootstrap.log
140118 17:06:19 [ERROR] An old style --language value with language
specific part detected: /usr/share/mysql/english/
140118 17:06:19 [ERROR] Use --lc-messages-dir without language
specific part instead.
140118 17:06:19 InnoDB: The InnoDB memory heap is disabled
140118 17:06:19 InnoDB: Mutexes and rw_locks use GCC atomic builtins
140118 17:06:19 InnoDB: Compressed tables use zlib 1.2.8
140118 17:06:19 InnoDB: Using Linux native AIO
/usr/sbin/mysqld: Can't create/write to file
'./mysql_myconnpy/cpy_server1/tmp/ibGc4rBM' (Errcode: 2)
140118 17:06:19  InnoDB: Error: unable to create temporary file; errno: 2
140118 17:06:19 [ERROR] Plugin 'InnoDB' init function returned error.
140118 17:06:19 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
ERROR: 1049  Unknown database 'mysql'
140118 17:06:24 [ERROR] Aborting

140118 17:06:24 [Note] /usr/sbin/mysqld: Shutdown complete
```

but the directory is there (and empty):

$ ls ./mysql_myconnpy/cpy_server1/tmp/ -ld
drwxr-xr-x 2 morph morph 6 Jan 18 17:06 ./mysql_myconnpy/cpy_server1/tmp/

How to repeat:
Run the unittests as follows:

PYTHONPATH=build/lib.linux-x86_64-2.7/ python unittests.py
--with-mysql=/usr/ --mysql-topdir=./mysql_myconnpy/ --verbosity=10
--bind-address=:: --host=::1

The problem is because of AppArmor, for more information you can see
https://blogs.oracle.com/jsmyth/entry/apparmor_and_mysql

In summary AppArmor restricts an application to use system resources.
In the mentioned case because of apparmor /usr/sbin/mysqld is not able
to create files inside tmp folder even when it has required permission.

To avoid this one of the three things can be done:
1> Update /etc/apparmor.d/usr.sbin.mysqld and add the path to the directory
where mysqld will write data
2> Disable apparmor for /usr/sbin/mysqld
3> change apparmor mode to complain form enforce for /usr/sbin/mysqld

Hello,
I'm not using AppArmor on my machine, so it can't be (only) that preventing to start the test instance.

Regards,
Sandro

Can you tell me which OS(with version number) you are using?

it's Debian Unstable (amd64, if it's worth to mention)

Re-opening; this should not have been closed.

This was a problem with relative directories when using the topdir command line argument. We did some more improvements to support system MySQL installation (thus not in it's on folder like /usr/local/mysql).

Fixed in 1.1.7.

Changes for test suite. No changelog entry needed.