In Commvault we support WORM on disk with deduplication and also on non-deduplication mode. 

In non-deduplication mode, we lock the files written with same number of days as of retention of the copies writing the data.

Whereas in deduplication mode, we work storage/storage pools. Here we will define retention and on the basis of retention value we will compute your DDB seal frequency. DDB seal frequency days value ranges from minimum of 7 days to maximum of 365 days.

if retention in days is:

1. less than or equal to 7 days, DDB seal frequency is set as 7 days.
2. if retention is from 8 to 365 days, seal frequency is set equal to retention in days. example retention is 30 days, DDB seal frequency is 30 days too.
3. If retention is 365 of more than 365 days, then DDB seal frequency is set as 365 days.

Next things is WORM lock days in deduplication. WORM lock days is sum of retention in days and DDB seal frequency. Pruning we support macro pruning only and this is done with sealing DDB regularly, once WORM lock is met for entire DDB store pruning is kicked off.

Hope this answers your question.

Thanks

Nikhil Gupta

Hello @Commvault Engineer 

You can review this document for more information about configuring WORM on Disk Libraries.

Enabling WORM Storage and Retention for Disk Storage - https://documentation.commvault.com/2023e/essential/155629_enabling_worm_storage_and_retention_for_disk_storage.html

Thank you,

Collin

Thanks a lot, @Nikhil Gupta, for your prompt feedback.

What about cycles, in this case, how can cycles affect the pruning process ?

Let’s say we have a storage policy copy with a retention set for 7 days and 1 cycle with WORM enabled on both CV and Storage Side. That means that the DDB seal will be setup for 7 days and on Storage Side has to be set up for 14 Days (Double of copy retention as per documentation). When does the first cycle gets pruned in this case ? Knowing that, after the first week's cycle, a new DDB is created (On week 2) and the first DDB (Week 1) is sealed. With my understanding, the first cycle can be pruned on the first day of Week 3, since on that day, we would have met all CV retentions requirements (Days and cycles) for the first full backup (On week 1), but still, from Storage side, the week 1 incrementals are still being protected with WORM since it’s set up for 14 days.

I know it’s a lot to digest, but this example would help us understand how the process actually works.

Could you also explain more for us what’s the difference between Macro and Micro pruning ? And how does both processes work ?

Thanks in advance.

@Commvault Engineer , 

As per 7 days and 1 cycle retention setting, we must always maintain a cycle for a sub-client. As soon as we have met days criteria, and we have another new cycle added on the copy; previous will qualify for aging.

In the case of WORM only the days wait increases due to sealing frequency consideration. 

About micro pruning, this is the pruning style where we will truncate files, drill holes in files or delete the entire file. macro pruning on the other hand is only entire file deletion.

Thanks

Nikhil Gupta