Backup Exec 2014 B2D Fragmentation Causing slowdown of Duplicates

[broadld]

Hi there,

Over time we seem to be getting slower and slower performance duplicating to tape.

Our simplified backup regime is as follows:-

Full backup B2D - Weekend then duplicated to tape

Differential backups B2D - Mon-Fri then duplicated to tape

We believe the issue is being caused by Backup exec not re using b2d files but creating new ones. As the B2D files expire they are deleted by data lifecycle management (DLM).

So every week the old b2d files are deleted then a new set is created which is causing more and more fragmentation each week.

How can you minimise this or eradicate the fragmentation? It is impossible to defrag the store in a timely manner due to the size of it. Is there any settings in Backup exec to prevent fragmentation from occuring?

I already have preallocating space enabled for the backup store as this is meant to help with fragmentation. I found this tip in another post.

A better way would be to re use the already created .bkf files and then we could keep on top of deframenting the drive as the files do not get removed and re created.

Any help would be great.

Thanks

David

[CraigV · Accepted solution]

...only way i can think of is to increase the size of the B2D files, but this in turn means that if you are including more data in less B2D files, you stand to lose more data if a B2D file corrupts.

There is no way to reuse a B2D file like tape...once it reaches its expiry data, DLM deletes it.

Thanks!

[broadld]

Hi Craig thanks for you advice on this. Unfortunately you are confirming what i thought already. We have already increased the file size as you have stated.

This is a bit of a poor design from Symantec as over time fragmentation will get worse. Eventually this wll then start impacting upon performance like we are seeing now.

[CraigV]

Yep, and unless your B2D device can do internal health checks and fix itself (so to speak) you're going to have to do this manually yourself.

Thanks!

[teiva-boy]

BackupExec + B2D + and fragmentation has always been an issue for more than 10+yrs now.  This isn't news.  We've always recommeneded running defrags on a regular schedule during non-backup hours.  Whether that is native defrag, or buying a product like DiskKeeper for a Server OS.

You can band-aid the situation some, if you pre-allocate the disk space on the B2D's.  You can also look into using faster disks.  Or use an OST device, which is the ultimate fix, but at a cost.