StoreOnce data integrity checksum?

[SerkanDemir]

Hello experts,

My company is looking into buying a Storeonce storage system. As I was researching I found something that concerned me about data integrity during deduplication. According to the Storeonce Deduplication whitepaper CRC checksum for data isn't done for NAS and Catalyst only for Virtual Tapes. So how does Storeonce facilitate data integrity for these protocols? Could someone explain?

Taken from Technical white paper Integrity Plus for HP StoreOnce Deduplication:

"For every block of virtual tape data, a cyclical redundant checksum (CRC) is generated and stored with the data on disk. When the data is read back, a CRC is re-computed and compared with the original, and any discrepancy reports an SCSI check condition. NAS and Catalyst emulations do not apply a CRC at this stage in StoreOnce systems because of the fundamental differences in their protocol from serial devices, e.g., NAS share data may be modified at the request of the host server. However, both NAS and StoreOnce Catalyst have rigorous checks applied at different stages while en route to the StoreOnce appliance."

[sbhat09]

Hello @SerkanDemir 

Can you please share the document link that you are referring? Let me try to check more details and get back to you.

Regards,
Srinivas Bhat

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[SerkanDemir]

Hello @sbhat09 

Here's the link for the paper I mentioned: https://docdro.id/2u5trA3

Thanks!

[sbhat09]

Hello @SerkanDemir,

Thanks for sharing the source document.

I checked further about this. Cyclical Redundant Checksum (CRC) doesn't apply on NAS and any catalyst emulations (not the regular StoreOnce catalyst stores) because the for those data types, the file system is managed by the hosts or some initiators outside the StoreOnce system. CRC applies for rest of the block volume backups like StoreOnce catalyst stores, VTLs etc. The exclusion is to avoid file system conflicts, not a downside of the product.

Regards,
Srinivas Bhat

If you feel this was helpful please click the KUDOS! thumb below!
Note: All of my comments are my own and are not any official representation of HPE.