How to permanently raise ulimit 'open files' and MySQL 'open_files_limit'
The default ulimit (maximum) open files limit is: 1024--Which is very low, especially for a web server environment hosting multiple heavy database driven sites.
This ulimit 'open files' setting is also used by MySQL. MySQL automatically sets its open_files_limit to whatever the system's ulimit is set to--at default will be 1024.
NOTE: MySQL can NOT set it's open_files_limit to anything higher than what is specified under ulimit 'open files'--you can set it lower, but not above the 'open files' limit.
Anyhow...
This is how we raise the ulimit
To check the limits:
ulimit -a
You will see something like: