The Database Manager is the database administration tool designed specifically for the MySQL MaxDB database. This section describes the Database Manager from the high availability viewpoint and recommends how you can use it to increase the availability of your MaxDB database.
The information in this section is a summary and is not intended to give you exact instructions. Always consult the MaxDB documentation before performing tasks with the Database Manager. For more information, see:
· Database Manager GUI – features a graphical user interface
· Database Manager CLI – features a command-line interface
· Monitoring data and log storage
You can use the Database Manager to see how full the database instance is. Use this information to schedule manual log backups if necessary to avoid downtime. A value of 100% in either case stops the database instance from processing, so preventing SAP applications from continuing.
To perform certain administrative tasks for high availability, you need to check which operational state the database instance is in.
· Background jobs
· Condition of log segments
You can activate AutoLog to automatically back up full log segments.
· Configuration of database instance
You can adjust the database instance using Database Manager as described below:
You can display and modify the configuration of the database parameters.
Ў Add Volumes
You can expand data and the log area (physical storage area) of the database instance by adding data and log volumes.
Ў Update system tables
You can update the system tables.
You can use the Database Manager to control and monitor the database system and to execute backup and recovery procedures. You can perform all monitoring functions available in the Database Manager using the database assistant in the CCMS of the SAP system. You can schedule backups in operational state ONLINE with the DBA Planning Calendar, part of CCMS.
The Database Manager lets you perform complete data backups, incremental backups (that is, a backup of only the modifications made since the last data backup), interactive backups of the logs. You can also activate the automatic log backup. The backup or recovery operations apply to only the addressed database instance.
Automatic log backups are performed using pre-defined parameters whereas ad-hoc data or log backups are performed interactively. Incorrect entries or a timeout due to delayed input can cause the backup to abort, possibly leading to downtime.
Each backup is done to a backup medium. The Media Manager supports parallel backups, allowing faster throughput in the case of backups.
Here are some recommendation for your backup strategy:
Incremental backups are most effective when the database modifications focus on particular database objects. Incremental backups generally increase the data volume of the backup but speed up the recovery times because only database pages have to be restored. A recovery using log backup always re-executes commands and this is more complex and time-consuming.
Back up the log area frequently.
If the log area fills up (that is, to 100%), the database instance automatically stops processing, leading to downtime for your SAP applications. Therefore, be sure to back up the log area regularly.
The best approach is to activate automatic log backup.
Accelerate backup and recovery using parallel backup devices.
To accelerate the backup and recovery operations for large database systems, use several backup devices working simultaneously in parallel. The backup and recovery times then depend on the number of backup devices used and on the disk capacity of the largest data volume.
Concepts of the Database System, Administration