Regarding retention policy

[Neelakantan]

Retention Policy 1:

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RETENTION POINTS 7 (Schedule job every hour, with synthetic backup enabled every day):
(DAY 1)--------------------------------------------------->(Day 2)
F1->I1->I2->...->I7->F2->I1->I2...->I7->F3->I1->I2...->I7-> F2->I1...

In 1 day, total 3 Full, 21 Increments

Retention Policy 2:

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RETENTION DAYS 7 (Schedule job every hour, with synthetic backup enabled every day):
(DAY 1)-------------------------------> (DAY 7)
F1->I1->I2->I3->... ( 24 X 7)... I168 -> F2->I1->I2...

In 7 days, total 1 Full and 168 Increments (7 Days X 24 jobs = 168 jobs)

Is my understanding correct for "Forward Incremental" method?

How the deletion of retention points be done, once the retention points fall out of the retention policy condition? will deletion be done automatically as part of backup job, or user need to explicitly configure the deletion jobs?

What would happen to deletion, say if the target storage repository is applying immutability policy?

[david.domask]

Hi Neelakantan,

Only one Synthetic Full will be created per day for a given job:

Veeam Backup & Replication creates a synthetic full backup only once a day on which synthetic full backup is scheduled. If you run the backup job again on the same day, Veeam Backup & Replication will perform incremental backup in a regular manner.

So you will have 23 increments produced + a Synthetic Full with such a schedule. See our explanation on Forward Incremental Retention here for more details.

Please check those details as they answer how the retention works and what you will have on the repository.

As for immutable backups, please see this section of the User Guide as it explains the behavior; in brief, Veeam is aware when you configure the immutability in Veeam and will handle the retention appropriately for immutable backup files once the backups are no longer immutable. Using immutability outside of Veeam will likely result in errors during retention if immutability is not complete for the file as Veeam will not be aware that the file is immutable.

[Neelakantan]

@david.domask, first of all thanks.

Please check my "Retention policy 1" again, there i have specified that fulls get created after every 7 restore point backups.

Is that true? or it will just create 1 full backup followed by all incremental until the synthetic backup that triggers in at the End of the day?

Is it possible to have multiple fulls in a day as i have specified in the diagram? if so, what job retention policy could achieve that(assume such a need is a requirement for a business workflow)?

Also, a follow up question,

will the deletion of the "old" backup chain be done, as part of the backup job itself, once retained backup count determined to be attained?
( or )
After backup job is done, some other process would come along to do that(like garbage collector), assume per VM separate chain backup?

Assume, a possibility some VM, due to failure, its chain does not have sufficient restore points(retained backup count)?

Sorry i could not follow up on this thread as i was away.

[Neelakantan]

veeam-backup-replication-f2/regarding-r ... 94010.html

Hi team,

could someone answer the pending queries in the "last message" of the above thread?

Thanks,
Neelakantan K.

[Mildur]

Hi Neelakantan

Please don't create new topics if you don't get an immediate answer. I moved your comment back to the original topic.
@david.domask is currently out of office and will answer after he is back. Or I will try later to answer your question.

Best,
Fabian

[david.domask]

Hi,

> Please check my "Retention policy 1" again, there i have specified that fulls get created after every 7 restore point backups.
> Is that true? or it will just create 1 full backup followed by all incremental until the synthetic backup that triggers in at the End of the day?

Not quite; Synthetic Fulls will be produced on the first eligible run of the scheduled Synthetic Full day, and as per the User Guide page on Synthetic Fulls, the Synthetic will only be performed once per day. So you will likely end up with more increments than you expect as explained above. Right now you'd need to use scripting to periodically create multiple fulls per day, but these will be Active Fulls, which may be a non-starter here.

>will the deletion of the "old" backup chain be done, as part of the backup job itself, once retained backup count determined to be attained?
> After backup job is done, some other process would come along to do that(like garbage collector), assume per VM separate chain backup?

It's part of the job (last step) and we have background retention as well: https://helpcenter.veeam.com/docs/backu ... ml?ver=120 Please review the documents here.

> Assume, a possibility some VM, due to failure, its chain does not have sufficient restore points(retained backup count)?

Can you elaborate on this point a bit more? I understand the question as "what happens during retention if a VM does not successfully backup"; in this case, there will be a warning in the session if the VM is completely unavailable from the hypevisor OR if it's available and just not successful in backing up there will be an error; unless you have Deleted Machine Retention enabled, nothing will happen to the backups until you take action to remove the VM from the job, resolve the issue with backing up the VM, or Detach or Move the VM's backups from the job, but perhaps I misunderstand your query.

[Neelakantan]

Thanks @david.domask.

"So you will likely end up with more increments than you expect as explained above.... scripting to periodically create multiple fulls per day, but these will be Active Fulls ..."

If that is the case, then what is the relevance of retention policy configuration(Say we have chosen, 7 "retention points" + Daily synthetic backup, with a schedule of every hour backup job)?
Our expectation from such configuration is [AF1->I11->...I17]->[AF2->I21->I22->..I27] ... as soon veeam reaches I27, it will delete the old backup chain [AF1->I11->I12...I17], as per "forward Incremental Backup" method.

Notation used is as below
AF<N> - Active Full <Nth chain>
I<N><M> - Increment <Nth chain> <Mth increment>

[david.domask]

Hi Neelakantan,

I think the misunderstanding here is that as I get it, you seem to understand that your configuration will produce a full backup every 7 backups; this is not the case however, as noted in the User Guide links I posted above about Synthetic Fulls; Active Fulls perform similarly when scheduled, so on a scheduled full day, you will not have multiple fulls created, you will have one created and subsequent runs will be incremental.

Check our KB here for animations on how retention works: https://www.veeam.com/kb1799 Keep in mind, as I noted above, the scheduled fulls will only be made once per day. To get those Active Fulls in there, you would need to schedule them with scripting or manually perform them.

[Neelakantan]

Yes @david.domask, indeed i am confused and did not understand.

Rather, it seems the VBR retention policy configuration (7-retention points/7-days policy) seems to be for deleting old backup chains.

Say if i have 7 retention points configuration, then once A full backup + 6 incremental be attained, before VBR would delete the old chain(how long ever be that old/previous chain be based on the schedule).

in case of 7 days retention configuration, A full + seven days of incremental backups must be formed/attained to delete any old chains formed earlier to the present/current 7 days of backup.

Its all independent of the job schedule configuration, am i correct?

[david.domask]

Overall correct; the job schedule only really would affect points based retention, but as you correctly stated, until a new backup chain (full backup + increments) appears and the new chain meets the retention requirements, the old chain will not be cleared by retention.

[Neelakantan]

@david.domask, excuse me if i am persisting with doubts..

"Overall correct; "

Why is it a qualified "overall" correct, what do i miss still to understand fully/clearly?

and

In this context -> "the job schedule only really would affect points based retention" - (what do you mean by this?)

if it is a "days" based retention, why & how job schedule would not affect the number of backups & clearing retentions? for example, 3 Days retention policy (+synthetic full at the end of 3rd day) and job schedule every 1 hour, then i will have 1 Full + 72 incremental (24 X 3, every hour job schedule) right? job schedule affects the chain length & .. So only on 6th day, old chain formed for 3 days would get deleted right?

[david.domask]

The main item is about how and when the retention will apply: https://helpcenter.veeam.com/docs/backu ... ml?ver=120 I realize it's a bit of a read, but basically, with day based retention, there is always a minimum of 3 restore points required, and then it will be based on the creation time of the backup file. Your statement had some slightly misleading statements but overall you get the idea that with Forward Incremental, retention will not occur until the next Full backup is made, so predicting your on-disk backup file count depends a lot on the frequency of the job running.

As for my statement, retention for day-based retention is triggered by a date-based trigger OR with points it is triggered by number of restore points. So with days, you can run the job 1000x a day and until the date of retention is reached, retention won't act on the chain.