BE 2010 Backup to Disk Issue

[ScottIT]

We have roughly 436 GB of data that we backup every night (full backup) on Backup to Disk.  The problem is, it takes forever for the IMG to allocate.  In fact, it appears to take 5-6 hours on average.  We have it set to allocate 512 GB of space to the backup currently.  When we first started doing this, with the exact same settings, it was taking 5-6 hours.  I'm at a loss as to why the allocation time takes 5-6 hours, but the actual backup only takes 5-7 hours.  Prior to this, the allocation would take no more than 2 hours.

[AmolB]

We have it set to allocate 512 GB of space to the backup currently

Is that the "max B2D file size" ?

In B2D folder properties set the max B2D file size around 30-50GB

[ScottIT]

It is set to 512 for maximum size.  What will setting it to 30-50 GB do in terms of overall performance?  Do you want me to still check the allocate maximum size for backup to disk files?

[teiva-boy]

This means it wont have to create a 512GB file.  Instead it will make multiple 30-50GB files as needed.  Generally, I never pre-allocate, I just make sure there is enough space.  But that introduces lots of file fragmentation.

Have you checked drive performance lately and fragmentation?

[ScottIT]

Interesting.  For a 436+ GB backup, what do you recommend as an ideal solution with the least amount of fragmentation?

[ScottIT]

The thing is, it was working for us allocating the space.  Now it's not.  Should I delete all my catalogs?  What are my options?

[AmolB]

Deleting catalogs will not help you, check fragmentation level on the disk and make changes to the B2D properties.

[ScottIT]

I forgot to mention that everything was working great prior to this.  One day, we had issues with a job, and I restarted the Backup Exec services.  After that, all the backup to disk folders went offline.  I had to re-enable each one of them.  That's when all of this started.  Like I said though, we were able to backup using 512 of allocated space in 5-6 hours tops.  It never took longer then that.  Every since the service restart, everything has been acting screwy.

I can think of one thing we can try:

Delete all media sets and re-create them.

Do you think that will help?

[ScottIT]

It was working just fine doing allocation.  The only thing I've done different is restart the backup exec services in the last 3 weeks due to a failed job.  Not sure why I should be doing something different.  Should I delete the media sets?