What is the recommended way to generate staggered snapshots? For example hourly that last for a couple days, daily that last a couple weeks, weekly that last a couple months, etc.
If you just create multiple separate schedules, is there a downside to having multiple snapshots taken simultaneously? So if the year starts with a sunday, I’ll have hourly, daily, weekly, monthly and yearly snapshots all taken at the same time at 0:00 on january 1st.
I tried to create a hourly schedule only from 1 to 23 (skip 0), and daily that skips the sunday, but then it fails because the weekly schedule doesn’t exactly fit in the monthly schedule.
I try and avoid overlapping the timestamps if I can. here’s an example - one of our production systems has a schedule like this (datasets with SMB shares)
Hourly - Every hour from 1:00 to 23:00 - Lifetime 1 week
Daily - Every Night at 00:00 (excluding 1st day of each month) - Life of 4-12 weeks
Monthly - First of every month at 00:00 - Life of 6-12months
There for a really critical smb share (lots of activity and rollback of an hour could cost $$) - the dataset has:
Every 10mins (excluding on the hours - btw 6am and 10pm) - Life of 1 Day
Followed by the rest
The main reason we avoid doing all day for our 10min one - is it just limits the amount of snapshots in “Previous Versions” as we had performance issues at different times. On our 20/30min ver - we tend to use the whole day.
Edit: You could also limit your under hourly to biz days - such as monday to friday.
Glad I searched this out! On the way into work I was wondering how it knew which snapshots to delete for hourly, weekly, monthly, etc. And I’m glad I wondered. Another thing to tweak tonight. Would be useful if it prompted you about the importance of naming the snapshots a bit more prominently in the documentation, and suggest how to name them, as I’ve double checked and there is nothing there about naming being important at all that I could see.
If I may ask a perhaps dumb question.
If you name the staggered snapshots differently, can the system use the existing snapshots for the next “stagger”? E.g. Use an hour snapshot for a monthly one.
Or does it always create a new monthly one?
Thanks,
Etienne
I mindlessly created my daily, weekly and monthly snapshots with a single naming scheme and, years after, it just works: Only one snapshot is created on Mondays and on the first day of the month, and this snapshot outlives its daily siblings as expected.
If you were to disable, or possibly delete your monthly snapshot task, then your daily snapshot task would/could/might erase your monthlies, since as far as its concerned, those monthlies, are daily snapshots.
Or put another way, there is no magic metadata which prevents the deletion of your monthly snapshots, other than the fact that you currently have a monthly snapshot task configured with the right retention.
OR if you are using very old snapshot tasks, do they still have the retention coded in the name ie “2y” or “6m” or something like that?
It is a custom name, without explicit retention time. But the retention policy works as expected, even when there are gaps because the replication source was off.
What would happen if I were to change the snapshot task is an open question, but I do not intend to change it, and I expect that the backup (“pull” replication) would retain what it holds.
It will prevent you from 
