On 05/15/2018 08:53 PM, Lofgren, Eric wrote:
> Having failed to fix the ugly partition system, we’re going for reconfiguring mysql to make it elsewhere. I followed this post to try to get the temporary directory to point to another partition: https://encylia.com/2015/02/06/how-to-change-the-mysql-tmp-location-on-centos/ by doing all of the following under sudo:
> 
> mkdir /home/mysqltmp
> chmod 1777 /home/mysqltmp
> 
> nano /etc/my.cnf
> 
> Add below line under the [mysqld] section and save the file:
> tmpdir=/home/mysqltmp
> 
> systemctl restart mysqld
> 
> This restart fails. If I restore the old my.cnf without the change, it works perfectly. Checking the log, it seems there’s a permissions issue:
> 
> 2018-05-16T00:01:05.211853Z 0 [Note] /usr/sbin/mysqld (mysqld 5.7.22) starting as process 5929 ...
> 2018-05-16T00:01:05.214159Z 0 [Note] InnoDB: PUNCH HOLE support available
> 2018-05-16T00:01:05.214186Z 0 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
> 2018-05-16T00:01:05.214191Z 0 [Note] InnoDB: Uses event mutexes
> 2018-05-16T00:01:05.214194Z 0 [Note] InnoDB: GCC builtin __atomic_thread_fence() is used for memory barrier
> 2018-05-16T00:01:05.214197Z 0 [Note] InnoDB: Compressed tables use zlib 1.2.3
> 2018-05-16T00:01:05.214202Z 0 [Note] InnoDB: Using Linux native AIO
> 2018-05-16T00:01:05.214382Z 0 [Note] InnoDB: Number of pools: 1
> 2018-05-16T00:01:05.214459Z 0 [Note] InnoDB: Using CPU crc32 instructions
> mysqld: Can't create/write to file '/home/mysqltmp/ibAcknwl' (Errcode: 13 - Permission denied)
> 2018-05-16T00:01:05.214535Z 0 [ERROR] InnoDB: Unable to create temporary file; errno: 13
> 2018-05-16T00:01:05.214542Z 0 [ERROR] InnoDB: Plugin initialization aborted with error Generic error
> 2018-05-16T00:01:05.214548Z 0 [ERROR] Plugin 'InnoDB' init function returned error.
> 2018-05-16T00:01:05.214551Z 0 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
> 2018-05-16T00:01:05.214554Z 0 [ERROR] Failed to initialize builtin plugins.
> 2018-05-16T00:01:05.214557Z 0 [ERROR] Aborting
> 
> Any clues as to what I’ve done wrong?
> 
> Thanks,
> Eric
> 

Moving the temporary file location is a bandage.  You really should be 
concerned with the full root partition.  It is going to affect the 
operation of more than just mysql.