before upgrading make sure to backup the my.cnf file if you wish to use your former settings
cp /etc/my.cnf /etc/my.cnf_bak_`date +%F`
better also to dump the current mysql data to somewhere else for backup.
remove the current mysql:
yum remove mysql55-server mysql55-libs mysql55-devel mysql55-bench mysql55
take note of the other applications this command removes – we would like to reinstall them later.
add the repository for the relvant mysql – 56 in our case:
cd /root/ wget http://dev.mysql.com/get/mysql-community-release-el6-5.noarch.rpm yum localinstall mysql-community-release-el6-5.noarch.rpm yum install mysql-community-server yum install crontabs mysqltuner yum-cron sysstat postfix
set the service to start on boot:
chkconfig --list mysqld chkconfig mysqld on chkconfig --list mysqld
start the service and upgrade:
service mysqld start mysql_upgrade
at this point i like to clear the log and restart the mysql to check for errors after the upgrade:
service mysqld stop echo :> /var/log/mysqld.log service mysqld start
now you can read the log and check for errors from this fresh upgrade.
if you have a tomcat working with the mysql server,
better stop the tomcat , clear its logs temp and work folders and restart to have it start clean.