Snapshot delete understanding

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1

Lets say when I run first snapshot it creates full backup
and my snapshot name is 08-29-2020

now I created another one tomorrow and by default it will do incremental named 8-30-2020

now I created third one which will be incremental named 8-31-2020

what on 1st September I delete 8-29-2020 and run backup

will it create full backup? named 09-01-2020?

I have try to read blog and document but I didn't understand. what happens when I delete that backup.

reason I am asking is that I run backup daily and delete backup older then 7 days before starting new one.

2

All snapshots are full. The incremental part refers to only new segments bring copied every time a new snapshot is created. This very old blog post describes it quite well and is still relevant as far as I know.

3

I already read this blog post. you posted this link on another thread

one more question and verification

that means by me deleting 8-28-2020 snapshot before running another snapshot give me whole index if I restore correct?

4

You always get the full index when you restore a snapshot.

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5

I also wrote a blog on how this works with different levels of detail, including deletes.

I do think it's confusing to call snapshots 'full', as to me they are incremental, but restores are always full restores. It's different than how DBMS do incremental, but to me any backup that only 'writes' changed data is incremental.

Maybe that's just from being an old DBA, but I bet this confuses a lot of folks and kinda wish the nomenclature were different (incremental snaps, full restores).

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6

good blog Steve, Thanks

7

Thanks and happily the latest ES docs use incremental terminology:

Snapshots are incremental: each snapshot only stores data that is not part of an earlier snapshot. This enables you to take frequent snapshots with minimal overhead.

8

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