| Bug #63632 | Cannot access database via symbolic link to a different filesystem | ||
|---|---|---|---|
| Submitted: | 6 Dec 2011 17:40 | Modified: | 7 Sep 2012 19:14 |
| Reporter: | Terry Tuck | Email Updates: | |
| Status: | Not a Bug | Impact on me: | |
| Category: | MySQL Server | Severity: | S3 (Non-critical) |
| Version: | 5.5.18-1, 5.5.20 | OS: | Linux (RHEL 5) |
| Assigned to: | CPU Architecture: | Any | |
[20 Dec 2011 16:26]
Sveta Smirnova
Thank you for the report. Please check: if you restart MySQL server after mounting different disk will it recognize the link? Please also indicate which filesystem this disk uses: I tested with ext4 and NTFS and everything worked fine.
[21 Dec 2011 18:27]
Terry Tuck
Thank you for working on this. No - rebooting server (which include mysqld restart) has no affect, and type of file system doesn't matter. Details from after reboot, and without performing manual mounts: [root@localhost ~]# cd /var/lib/mysql [root@localhost mysql]# cat /etc/fstab /dev/VolGroup00/LogVol00 / ext3 defaults 1 1 LABEL=/boot /boot ext3 defaults 1 2 tmpfs /dev/shm tmpfs defaults 0 0 devpts /dev/pts devpts gid=5,mode=620 0 0 sysfs /sys sysfs defaults 0 0 proc /proc proc defaults 0 0 /dev/VolGroup00/LogVol01 swap swap defaults 0 0 /dev/sdb1 /mantis-filesystem ext4 defaults 0 2 /dev/sdc1 /mantis ext3 defaults 0 2 [root@localhost mysql]# ls -ld * lrwxrwxrwx 1 mysql mysql 12 Dec 21 11:47 ext3 -> /mantis/ext3 lrwxrwxrwx 1 mysql mysql 34 Dec 21 11:47 ext4 -> /mantis-filesystem/mysql_data/ext4 -rw-rw---- 1 mysql mysql 18874368 Dec 21 12:05 ibdata1 -rw-rw---- 1 mysql mysql 5242880 Dec 21 12:09 ib_logfile0 -rw-rw---- 1 mysql mysql 5242880 Dec 6 07:38 ib_logfile1 drwx--x--x 2 mysql mysql 4096 Dec 6 07:29 mysql srwxrwxrwx 1 mysql mysql 0 Dec 21 12:09 mysql.sock drwx------ 2 mysql mysql 4096 Dec 6 07:29 performance_schema -rw-r--r-- 1 mysql mysql 113 Dec 6 07:29 RPM_UPGRADE_HISTORY -rw-r--r-- 1 mysql mysql 113 Dec 6 07:29 RPM_UPGRADE_MARKER-LAST -rw-rw---- 1 mysql mysql 5 Dec 21 12:09 localhost.pid [root@localhost mysql]# su mysql bash-3.2$ cd ext3 bash-3.2$ ls -l total 8 drwxr-xr-x 2 mysql mysql 4096 Dec 21 12:04 testdirectory1 bash-3.2$ cd ../ext4 bash-3.2$ ls -l total 4 drwxr-xr-x 2 mysql mysql 4096 Dec 21 12:05 testdirectory2 bash-3.2$ mysql -u root -p Enter password: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 2 Server version: 5.5.18 MySQL Community Server (GPL) Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | mysql | | performance_schema | +--------------------+ 3 rows in set (0.00 sec)
[22 Dec 2011 17:29]
Sveta Smirnova
Thank you for the feedback. Which package do you use (filename you downloaded)? Could you please try with latest binary available from dev.mysql.com/downloads?
[23 Jan 2012 1:00]
Bugs System
No feedback was provided for this bug for over a month, so it is being suspended automatically. If you are able to provide the information that was originally requested, please do so and change the status of the bug back to "Open".
[25 Jan 2012 17:18]
Michael Shestero
I have the similar problem width two ext3 systems. mysqld Ver 5.1.41-3ubuntu12.10 for debian-linux-gnu on x86_64 ((Ubuntu)) see also: http://rsdn.ru/forum/db/4590487.flat.aspx
[26 Jan 2012 17:11]
Terry Tuck
The file used was MySQL-server-5.5.18-1.rhel5.x86_64.rpm
[30 Jan 2012 20:11]
Sveta Smirnova
Thank you for the feedback. Do yo have SELinux enabled?
[30 Jan 2012 23:52]
Sveta Smirnova
I can not repeat described behavior with indicated package as well. Please also check user rights for mounted device: check mount output after you mounted it and mount options you used.
[2 Feb 2012 22:53]
Terry Tuck
Sveta: thank you for continuing on this. No SELinux No quotas in use on system filesystems mounted via fstab, using arguments: /dev/sdb1 ext3 defaults 0 2 /dev/sdc1 ext4 defaults 0 2 Problem also exists when using MySQL-server-5.5.20-1.rhel5.x86_64.rpm and MySQL-server-5.5.20-1.rhel5.i386.rpm I'm using mysql_secure_installation after install.
[7 Sep 2012 18:56]
Sveta Smirnova
Thank you for the feedback. Please send us your configuration file also.
[7 Sep 2012 19:02]
Terry Tuck
This was indeed a SELinux issue. After SELinux was disabled all problems were resolved. To check if SELinux is running: ls /selinux if the directory is empty, then not running. If NOT empty, then set SELinux to disable enforcement. Sveta: my apologies for time you spent on this.
[7 Sep 2012 19:14]
Sveta Smirnova
Thank you for the feedback. Closed as not a bug.
Description: Cannot use symbolic link created within mysql data dir to represent a database stored on a filesystem other than the system disk. (symbolic links work correctly when target is on system disk.) How to repeat: Following instructions listed in section 7.11.3.1.1 of refman-5.5: 1. Mount a different filesystem 2. in data dir, as user running mysqld, create symbolic link to different filesystem. 3. as user running mysqld, navigate symbolic link to test access privs at target 4. in mysql, use 'show databases' to see that symbolic link is not recognized as db-path/database. Details of steps: [root@localhost /]# mysqld --verbose --help | grep symbolic 111206 11:21:56 [Note] Plugin 'FEDERATED' is disabled. -s, --symbolic-links Enable symbolic link support. (Defaults to on; use --skip-symbolic-links to disable.) symbolic-links TRUE [root@localhost /]# cd /var/lib/mysql [root@localhost mysql]# mkdir /system_disk [root@localhost mysql]# chown mysql:mysql /system_disk [root@localhost mysql]# su mysql bash-3.2$ ln -s /system_disk . bash-3.2$ cd system_disk bash-3.2$ touch test-file bash-3.2$ ls -l total 4 -rw-r--r-- 1 mysql mysql 0 Dec 6 11:24 test-file bash-3.2$ rm test-file bash-3.2$ exit exit [root@localhost mysql]# mount /dev/sdc1 /dev/different_disk [root@localhost mysql]# su mysql bash-3.2$ ln -s /dev/different_disk . bash-3.2$ cd different_disk bash-3.2$ touch test-file bash-3.2$ ls -l total 20 drwx------ 2 root root 16384 Dec 5 20:19 lost+found -rw-r--r-- 1 mysql mysql 0 Dec 6 11:25 test-file bash-3.2$ rm test-file bash-3.2$ exit exit [root@localhost mysql]# ls -l total 28776 lrwxrwxrwx 1 mysql mysql 19 Dec 6 11:25 different_disk -> /dev/different_disk -rw-rw---- 1 mysql mysql 18874368 Dec 6 11:01 ibdata1 -rw-rw---- 1 mysql mysql 5242880 Dec 6 11:01 ib_logfile0 -rw-rw---- 1 mysql mysql 5242880 Dec 6 07:38 ib_logfile1 drwx--x--x 2 mysql mysql 4096 Dec 6 07:29 mysql srwxrwxrwx 1 mysql mysql 0 Dec 6 11:01 mysql.sock drwx------ 2 mysql mysql 4096 Dec 6 07:29 performance_schema -rw-r--r-- 1 mysql mysql 113 Dec 6 07:29 RPM_UPGRADE_HISTORY -rw-r--r-- 1 mysql mysql 113 Dec 6 07:29 RPM_UPGRADE_MARKER-LAST lrwxrwxrwx 1 mysql mysql 12 Dec 6 11:24 system_disk -> /system_disk [root@localhost mysql]# mysql -u root -p Enter password: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 3 Server version: 5.5.18 MySQL Community Server (GPL) Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | mysql | | performance_schema | | system_disk | +--------------------+ 4 rows in set (0.00 sec) mysql>