We use both here and have been for over 4 years.  We use Data Domain for all of our data center backups and Puredisk (the original appliance based version) for all of our remote file server backups.  We did look into Netbackup 7’s built in dedupe which uses the puredisk dedupe engine to allow both client side and media server dedupe of backups to any disk storage backends but just couldn’t get the compression we get out of the data domain appliances.  As an example, our data domains currently house approximately 35 copies of our exchange backups (700GB during a full backup) in 3.8TB of raw.  We presented the same amount of storage from a dell equallogic storage array to a netbackup dedupe pool and we couldn’t fit 4 copies of that same exchange data. 

 

We’ve done countless reference calls for Data Domain detailing our consideration of Netbackups built in dedupe and our findings.  The biggest problem is the Netbackup Puredisk dedupe uses a fixed block algorithm where as the Data Domain’s use a variable block algorithm.  This allows the Data Domain appliances to generate much greater compression. 

 

The backup performance was comparable across both solutions but just like we’ve seen with our appliance based puredisk environment, restores from the Data Domain’s were MUCH faster than from the puredisk storage.  Netbackup 7 has improved the restore speeds but it’s still not comparable to the 100GB /hour restore speeds we get (simultaneously across multiple platforms / applications) at our Disaster recovery exercises.  In our production puredisk environment, if we need to restore a 100GB file server to ship out to a plant it can take up to 10-12 hours to restore.

 

If you have a HUGE pool of money to spend on back end disk then Netbackup 7’s built in dedupe may still be an option for you.  However, we’d have needed to purchase more than 10X the raw disk capacity of our data domain appliances in order to be able to house the same amount of deduped data that our Data Domain’s currently store.  As existing Data Domain customers, this was not financially viable and even the lure of a one stop shop for all backup storage was not big enough for us to jump ship after 4+ years as Data Domain users.

 

We started off with two dd430’s and later added two dd560’s.  Now have two DD670’s setup in a replication pair and use Storage Lifecycle Policies (SLP’s) inside Netbackup coupled with the optional Open Storage (OST) plugin to manage all but a handful of backup policies.  The OST plugin lets us make use of the Optimized duplication technology to reduce bandwidth utilization between our main data center and our DR site and the tighter integration with Netbackup gives us additional visibility of both our primary and now also our duplicated images from inside the catalog.

 

Yes… I’m a Data Domain fan but that’s not because I’m getting paid to say this stuff.  It’s because it works flawlessly, has got us out of some real binds and makes my boss look like a rockstar at our twice yearly DR tests.  If we’d seen similar numbers from Netbackup then I’d be singing a different tune but for now, Data Domain has my vote.

 

Mark Glazerman

Desk: 314-889-8282

Cell: 618-520-3401

P please don't print this e-mail unless you really need to

 

 

Hi all,

My employer is requesting I evaluate PureDisk and DataDomain for de-duplication. While I can setup a demo of each and get the numbers, and ask the sales guys what makes them great and why their competitors aren't, I can't trust that is nothing more than sales drivel. So, I ask you expert users. Can anyone tell me what their experiences are with DataDomain and PureDisk and why you went with that solution from a technical perspective? You know, the typical pro/con deal.

Thanks for the help!
~~Fred~~