Hi Skip.
The “pre-allocate” is when Backup Exec goes and pre-creates the complete *.bkf file.
So if you set your B2D device to use 10GB file sizes, it will create the 10GB file before the actual backup starts. The benefit to this is that the fragmentation on the disk is a lot less, even non existent. Needless to say the less fragmentation the better your disk performance.
If this setting is not ticked, the backup job will create the*.bkf file as it is backing up. This leads to huge fragmentation issues.
The performance also degrades when duplicating to tape, since BE is now reading from the disk where the fragmentation is high.
This setting is under the properties tab of the Backup to Disk folder. I do not have the GUI open in front of me so I am not sure about the exact wording. Look out for the “pre-allocate file sizes” selection, and select the tick. (Make the file sizes to your own preference. We use 10GB file sizes.(You can imagine how many files will be created when you have 2TB to backup, using 1GB file sizes))
Once you have done that, go to your Media Set tab and create / edit a Media set so that appendable = 0hours, and the protection is set to your preference. Now make sure that your backup Jobs that write to Disk uses the Media set you created / edited.
(Note that when your backup job start it might take some time before you see progress, as it firsts go and “prep” the disk.)
This should sort out the ADAMM issues you guys are experiencing.
Cheers
No problem. Please keep this thread running still and provide your feedback here.
