MySQL troubleshooting
Just in case you are facing downtime issues on MySQL on CentOS try these.
Check if disk is full
- df -h
if disk is full check which folder is occupying lot of space.
- cd /
- du -skh *
Then go into individual folders to check if files can be deleted. If mysql/ folder looks like culprit, below steps might be useful.
If mysqld.log is big, trim it.
- sudo echo -n > mysqld.log
In case there are 1.1GB files with sequence file numbers, e.g. xxx.00001, xxx.00002 etc, in /var/lib/mysql. Delete them.
- cd /var/lib/mysql/
- sudo service mysql stop
- sudo rm -f xxx.0*
- sudo service mysql start
If mysql is not allowing you to stop, kill it.
- sudo kill -9 <<process_id_of_mysql>>
- sudo rm -f xxx.err
- sudo service mysql start
If mysql says Starting MySQL.The server quit without updating PID file try these
- mysql_install_db
- sudo service mysql start
If none of these work, dont loose faith.. Ask Google.
Still issues? ask a DBA.
Still issues? prepare to put down your papers.