MySQL DBA Responsibilities

 DBA Responsibilities

Server startup/shutdown
Mastering the mysqladmin administrative client
Using the mysql interactive client
User account maintenance
Log file maintenance
Database backup/copying
Hardware tuning
Multiple server setups
Software updates and upgrades
File system security
Server security
Repair and maintenance
Crash recovery
Preventive maintenance
Understanding the mysqld server daemon
Performance analysis
Obtaining and Installing MySQL

Choosing what else to install (e.g. Apache, Perl +modules, PHP)
Which version of MySQL (stable, developer, source, binary)
Creating a user acccount for the mysql user and group
Download and unpack a distribution
Compile source code and install (or rpm)
Initialize the data directory and grant tables with mysql_install_db
Starting the server
Installing Perl DBI support
Installing PHP
Installing Apache
Obtaining and installing the samp_db sample database
The MySQL Data Directory

deciding/finding the Data Directory’s location
Structure of the Data Directory
How mysqld provides access to data
Running multiple servers on a single Data Directory
Database representation
Table representation (form, data and index files)
OS constraints on DB and table names
Data Directory structure and performance, resources, security
MySQL status files (.pid, .err, .log, etc)
Relocating Data Directory contents
Starting Up and Shutting Down the MySQL Server

Securing a new MySQL installlation
Running mysqld as an unprivileged user
Methods of starting the server
Invoking mysqld directly
Invoking safe_mysqld
Invoking mysql.server
Specifying startup options
Checking tables at startup
Shutting down the server
Regaining control of the server if you can’t connect
Managing MySQL User Accounts

Creating new users and granting privileges
Determining who can connect from where
Who should have what privileges?
Administrator privileges
Revoking privileges
Removing users
Maintaining MySQL Log Files

The general log
The update log
Rotating logs
Backing up logs
Backing Up, Copying, and Recovering MySQL Databases

Methods: mysqldump vs. direct copying
Backup policies
Scheduled cycles
Update logging
Consistent and comprehensible file-naming
Backing up the backup files
Off-site / off-system backups
Backing up an entire database with mysqldump
Compressed backup files
Backing up individual tables
Using mysqldump to transfer databases to another server
mysqldump options (flush-logs, lock-tables, quick, opt)
Direct copying methods
Database replication (live and off-line copying)
Recovering an entire database
Recovering grant tables
Recovering from mysqldump vs. tar/cpio files
Using update logs to replay post-backup queries
Editing update logs to avoid replaying erroneous queries
Recovering individual tables
Tuning the MySQL Server

Default parameters
The mysqladmin variables command
Setting variables (command line and options file)
Commonly used variables in performance tuning
back_log
delayed_queue_size
flush_time
key_buffer_size
max_allowed_packet
max_connections
table_cache
Erroneous use of record_buffer and sort_buffer
Running Multiple MySQL Servers

For test purposes
To overcome OS limits on per-process file descriptors
Separate servers for individual customers (e.g. ISPs)
Configuring and installing separate servers
Procedures for starting up multiple servers
Updating MySQL

Stable vs. development releases
Updates for both streams
Using the “Change Notes”
Bug fixing vs. new features
Dependencies on the MySQL C client library (PHP, Apache, Perl DBD::mysql)
MySQL Security

Assessing risks and threats
Internal security: data and directory access
Access to database files and log files
Securing both read and write access
Filesystem permissions
External security: network access
Structure and content of the MySQL Grant Tables
user, db, host, tables_priv, columns_priv
Grant table scope fields/columns
Grant table privilege columns
Database and table privileges: ALTER, CREATE, DELETE, DROP, INDEX, INSERT, SELECT, UPDATE
Administrative privileges: FILE, GRANT, PROCESS, RELOAD, SHUTDOWN
Server control over client access: matching grant table entries to client connection requests and queries
Scope column values: Host, User, Password, Db, Table_name, Column_name
Query access verification
Scope column mmatching order
Grant table risks: the FILE and ALTER privileges
Setting up users without GRANT
The anonymous user and sort order
MySQL Database Maintenance and Repair

Checking and repairing tables
Invoking myisamchk and isamchk
Extended checks
Standard table repair
Table repair with missing/damaged index or table description
Avoid server-checking interaction, without shutdowns