Server Setup | Security | Performance Tuning | …

Run mysqlcheck to fix SQL index/.. errors and clean the caches once in a while. this can be used as a weekly cronjob, the output is sent by mail:

 mysqlcheck -A -r --host=${HOST}  --user=root --port=3308 \ 
 --password=${PASSWD} | mail -s '[SQL Server] mycheck complete' $EMAILADDI

dump a database to a .sql file. there are many parameters. check 'man mysqldump'

–opt is important to fix encoding!

 mysqldump --opt --host=127.0.0.1 --default-character-set=utf8 --user=root --password=${PWD} $DB > $FILE

works by piping an sql file into the 'mysql' command:

 mysql --host=127.0.0.1  -u root --port=$PORT --password=${DBPWD} ${DBNAME} < ${MYSQLDUMP_FILE}

any sql statement can be executed in commandline and scripts by using '-e' param:

 mysql --host=127.0.0.1  -u $DBUSER --password=${DBPWD} --port=$PORT \ 
 -e "CREATE DATABASE ${DBNAME} DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci;"

there is a good chance to find the pass in root's commands history ;)

 cat /root/.mysql_history|more
 cat /root/.bash_history|more

if you are not lucky, you can put the mysql-server in recovery mode:

 /etc/init.d/mysql stop
 mysqld_safe --skip-grant-tables &   # start server wo/ permission checks..
 mysql -u root  # the SQL console is accessible without passwd..

 # change the pass in SQL:
 mysql> use mysql;
 mysql> update user set password=PASSWORD("NEW-ROOT-PASSWORD") where User='root';
 mysql> flush privileges;
 mysql> quit

 # restart in normal mode - with the fresh pass:
 /etc/init.d/mysql stop
 /etc/init.d/mysql start

Thanx for the infos to Vivek! http://www.cyberciti.biz/tips/recover-mysql-root-password.html