Choosing Backup Software Dedupe or PBBA? Six Important Criteria You Need to Consider

If you’re like most IT professionals working today, you’ve undoubtedly heard about deduplication as a time and money saving technology used in primary storage as well as backup environments. Because of the potential for saving money with backups that’s where most companies will deploy this technology.  However, deciding how to best deploy the technology can be confusing because deduplication is in both backup software applications as well as Purpose-Built Backup to Disk Appliances (PBBAs).  So with the wealth of products on the market that offer this attractive feature, what criteria should you look for when trying to choose the right product to use in your backup environment?

If you’re happy with your backup application and are currently using its’ internal deduplication functionality this may be the obvious choice.  However, there are some risks to concentrating all the deduplication efforts into one software basket that you should be aware of.  To help you make the right choice, here’s a list of the six major criteria you need to consider.

1) Media Server congestion - software dedupe can overload media servers as they must now process client backup data, perform hashing of the ingested data, manage the dedupe dictionary, create tape copies, process rehydration of data, and handle replication.  That’s a whole lot of tasks!  To solve this workload increase many companies add more media servers which increases costs and complexity.  Using a PBBA you can avoid these logjams since the appliance absorbs all these additional functions, leaving the media servers to do what they do best – process and move data.

2) Costs – as backup data workloads grow so do the needs for speed and efficiency.  Backup software vendors will promote their deduplication solutions as integrated and cost effective. However this approach requires investments to beef up media server CPU and memory in order to distribute the deduplication workloads.  Another method used to boost efficiency is utilization of Solid State Disks (SSDs) to store backup workloads.  Both of these approaches require additional investments, so when you consider the total cost of each approach – the additional expenses needed for a software approach washes out any expected savings.

3) Management and Maintenance – even though deduplication helps to reduce the amount of storage needed to house backups, if you’re using a backup software application you still need to manage the target repository requirements.  Simply adding additional HDDs to your existing storage pool will help but it means more time is needed to configure the environment, manage the LUNs, RAID groups, etc.  Using a PBBA removes this complexity since the appliance handles the placement of data on disk seamlessly without storage administrator attention.  Expansion of the appliance to handle data growth is easy since additional shelves of capacity are simply added to the existing appliance and the appliance operating system handles management of the additional disk space.

4) Flexibility – who knows what the future will hold for your backup environment? Because all data sets aren’t the same, your environment may benefit from having the flexibility to use more than one backup application to fit the organizations’ protection and recovery needs.  Using an appliance to handle deduplication tasks gives you the flexibility to adjust to changes and modifications – just add a new backup application and use the existing appliance to store the resulting backup datasets.  

5) Risk Tolerance – software based dedupe solutions are piggybacked on top of media servers running well-known, full-blown Operating Systems.  The downside to this fact is that well-known operating systems are open to viruses, worms and other malware.  On the other hand, the advantage of the closed operating systems used by PBBAs is the added layer of security since the operating systems are less open to corruption which might lead to data loss.

6) Rehydration – rehydrating data in a disk to disk to tape (D2D2T) scenario can be long and resource intensive.  This makes the use of backup software based dedupe solutions difficult to size since it puts additional rehydration strain on the shoulders of media servers.  On the other hand, using backup appliances removes this burden since they absorb all rehydration tasks from the backup environment, making it  easier to size the overall capacity needed to handle overall backup storage needs.

So if you’re considering which deduplication path to follow, let these six criteria be the guideposts that can help you reach your goal of overall backup environment efficiency.  To learn more read this informative white paper: Choosing the Right Deduplication Solution for Your Organization.