The complete database is backed up. A cumulative that is, incremental backup image. An incremental backup image is a copy of all database data that has changed since the most recent successful full backup operation. A non-cumulative that is, delta backup image. A delta backup image is a copy of all database data that has changed since the most recent successful backup operation.
Additional options. Backup is to be compressed. Only choose this option if you want to perform an online backup. Only those log files are included in the backup that are required to get a consistent database.
Any further log files are not taken into consideration. The following options are available for downward-compatibility reasons and we strongly recommend that you do not set them:. When performing a backup, you should consider the following:. The backup, however, remains on the database server unless a storage management product, for example, Tivoli Storage Manager TSM , is used.
Thus, an online backup has a complete set of archived log files that are available for database recovery. You have to back up partition by partition. Therefore, you have to schedule backup jobs for each partition. In a multi-partitioned database system, keep a copy of file db2nodes.
A subset of tablespaces should only be used in specific situations. You can optionally tell DB2 to compress the backup while it is being taken. This is a good option if you are taking backups to disk. You can also compress the backup after it is taken using the gzip or your favorite compression command.
This method has the advantage of reducing the backup duration, but it requires more disk space, more overall time, and may require more time on restore as the backup image has to be uncompressed before it can be used. My favorite backup syntax is usually:. By default, online DB2 backup images include the transaction log files that were written to while the backup was being taken.
No other transaction log files are included in the backup image. Both the structure and data of all objects in the database are included in the backup image. The backup also includes the database history file and the database configuration though these are only part of restore in specific circumstances. Data I collect regularly includes:.
Some of these items are included in database backups, but it may be hard to extract only a small part of the data from a backup. Is it increasing the backup performance or take the backup simultaneously in multiple streams divided the backup image into segments. So is it checking the same image 3 times or it is just 3 segments of a backup image.
Could you please let me know. You can use db2adutl commands to extract a backup image to disk assuming you have disk with enough space so you can play with it in a more familiar environment.
I know that specifying more than one session only helps performance if you have fully separate paths to your TSM server — specifying multiple sessions when it all goes over the same adapters and same link is not going to make much difference.
You can either take the backup to TSM or to disk, not both. There are commands to extract a backup taken to TSM to disk using db2audtl. Your email address will not be published. Notify me of follow-up comments by email. Notify me of new posts by email. Online backups on the other hand, can be performed while users are still connected to databases. Trove currently supports full offline backups for DB2. In this spec, we explain how to enable full online backups for DB2 in Trove.
As mentioned above, the difference between offline and online backup is that in the former case all applications must disconnect from the database while in the latter, applications can still be connected to databases while backup is being taken.
In order to enable online backups, archive logging needs to be enabled. This allows applications to use the database even while backups are being taken. Any updates made to the database is recorded in the logs. Logging is a mechanism where every updates to a database is recorded to transaction logs also called active logs as the data is being modified. There are 2 types of logging mechanism - circular and archive logging. By default, circular logging is enabled which means that after the last active log is filled, the first active log is overwritten.
With circular logging as the default logging mechanism, only offline backups can be taken.
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