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What is GBAK SCHEDULER — InterBase / Firebird Backup Windows Tool (gbaksvc - Windows service & gbakschd - GUI)

The main feature is to preserve a required number of  backups to allow data recovery for previous days. 

GBAK Scheduler keeps several InterBase / Firebird backups on your disks  (for example 4 a day for 30 days) so you can solve your possible database problem with the preferred copy (not always the last).  

GBAK Scheduler is safe because it doesn't perform InterBase / Firebird backup itself, but runs your copy of GBAK.EXE.

GBAK Scheduler uses few system resources and can run as an application or a Windows NT service. It can run in automatic (loaded and started at startup) or manual mode and can run 
your backup tasks whenever you want with the Execute now!  command, without waiting for the scheduled time.

It's easy to setup your backup schedule using Gbak Scheduler GUI tool.

Gbak Scheduler was tested on server platforms from Windows NT4 to  Windows 2012 Server and on client platforms from Windows 95 to Windows 8 (32 & 64 bit).

What is GBAK — InterBase / Firebird Backup and Restore

GBAK is Firebird's command line tool for online backup and restore of a complete database.

GBAK is able to perform a backup while the database is running. There is no need to shut down the database during a GBAK backup. GBAK will create a consistent snapshot of the database at the time it starts running. You will, however, notice a perfomance degradation during the backup, so it is a good idea to backup at night. As GBAK visits all pages of the database, it will also perform a garbage collection on the database.

You can find the official Firebird GBAK documentation here.

How Backup works:

GBAK will create a consistent snapshot (or dump) of a database. This snapshot/dump will contain the contents of the database of the point in time when the backup is started. For that, it will create an (one) isolated transaction that is used to read the entire database and write it to the snapshot/dump file (which ususally has the .fbk filename extension).

During the backup, the database can be used regularly. All transactions that run after the backup has started, will be separated from the backup. Depending on the size of the database, the duration of the backup and the number and duration of parallel transactions, this can more or less reduce the performace of the database while the backup is running (remember that Firebird has to handle all the data so that new data is isolated from the currently running backup). But it will work and after the backup is finished (the transaction is committed), the database will come back to its usual performance.