WORM with backup storage appliance

  • 5 March 2024
  • 1 reply

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Please can you help me with the following:

I would like to know how does WORM work with appliances like Data Domain or StoreOnce in comparison with object storage systems, where the needed capacity is doubled when using object lock. Is the capacity requirement for backup storage appliances also doubled?

Thanks in advance!


Best answer by Ted P 6 March 2024, 18:53

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Hi Sergio,

The effect of needing the extra capacity comes into play when using Commvault deduplication as we need to keep all the referenced data together in a “vault” since it can only macro prune.  Due to this we seal the DDB and create a new vault which will have a new baseline (which causes the increase in capacity).  We can write new data and lock it on the new vault, while the old one ages until it expires at which time it can get pruned.

If you are using something like our Data Domain Boost Access integration in combination with CV deduplication, the mechanism will be the same, but the Data Domain should be able to get a decent reduction between our baseline backups which will lower the storage utilization.  This would also apply to any storage device that has built in deduplication such as a VAST array.

If you are using HPE StoreOnce or Data Domain Boost Client integrations (both support WORM storage locks), these do not use CV deduplication, instead we leverage the dedupe engines of the storage itself.  In these cases, our Full / Syn Full backups are always full baselines which the storage deduplicates and not subject to the “vaulting” above as there is no CV DDB involved.  We can lock the data on the storage for the duration of our retention, and then prune those jobs when they age as normal.

When it comes to the economics of the solution, keep in mind that general object storage is typically cheaper per GB than a backup appliance.