How to preserve Snapvault Snapshot for 7 years in the secondary / DR storage system?

[SNETAPPUSER]

Hello,

Being a financial institution, it is required to retain monthly backups for 12 months and yearly backups for 7 years. However, since there is NO tape backups and ONLY Snapvault is there between both primary and secondary storage system, the challenge is to retain those Snapshots for that longer period of time with the significant amount of rate of change in data.

The requirement is something like this...

Take Snapvault Snapshot from Primary storage system and replicate it to Secondary storage system and in that the vaulted Snapshot should be retained for 7 years (for case of yearly backups). However, we cannot keep a Snapvault Snapshot in Primary system for year until the second one occurs because, with rate of data change we have in our systems, it would be a total waste of space, if we retain a Snapshot for a year's time in the Primary storage system.

In this kind of situation, how do we manage to retain vaulted Snapshots for that many years? (We, know that with Data Domain it would be much easier because, it appears as a tape (actually a VTL) to the system and DD is capable of managing that many retention times with its Dedup and Compression). Any ideas on How NetApp addresses this sort of scenarios with its Snapvault technology?

Thank you in advanced.

[aborzenkov]

You probably misunderstand how SnapVault works. Snapshots on primary and secondary are independent. You only need to keep the latest (base) snapshot on primary to allow incremental updates. All previous snapshots can be removed.

[SNETAPPUSER]

What you are telling is true and I know that.

The problem arise (in case of monthly and yearly backups), when it is required to keep the latest monthly and yearly backups for one month and one year's time within the Primary storage system itself in order to trigger next incremental update.

Considering the rate of change, for the case of daily and weekly backups, keeping latest Snapshot on the primary storage is not a big issue. But what about for monthly and yearly Snapshots on Primary side? That Snapshot can grow huge in size.

Any idea on how to address it?

[aborzenkov]

You can do incremental updates as often as you want. You do not need to create snapshots for these incremental updates on secondary and, as I already said, you need to keep only the latest baseline snapshot in any case.

[SNETAPPUSER]

Can explain how to implement it with some example? Then it would be much easier to understand my requirement and what you're saying..

Say, On the PRIMARY storage system there is a volume called SV_PR and on the SECONDARY storage system there is a volume called SV_DR

My backup windows and retention periods are as follows...

Every 4 Hour  2 Days

Every Day     2 Week

Weekly        12 Week

Monthly       12 Months

Annually      7 Years

In the case of above retention policies, how do you establish & maintain relationship between SV_PR and SV_DR while maintaining aforementioned retention periods on DR storage system?

I am kindly requesting you to give a configuration example... That would be a great help

Thank you in advanced.

[aborzenkov]

Use external scripting to create snapshots on secondary every month and year and keep them for required period of time. You will need to do it anyway, Data ONTAP does not provide any built-in capabilities to schedule snapshots with month or year period.

[SNETAPPUSER]

Do you any sample script like that? Can you show me one such example.

Thank you.