[DRBD-user] Backup frequency

[Robert Altnoeder]

Your guess is correct, the controller is transaction-safe, so if it confirms the creation of a resource, it will also have updated the database. If the controller or the database cannot make the change, the entire transaction rolls back.
The situation may be more complicated if etcd is used instead of a database, because as far as I recall, etcd is only “eventually consistent”, so some nodes may still be behind - but I don’t know the details of that, so don’t take my word on it. With the SQL databases, everything works as you would expect it to work for a committed SQL transaction.

Best regards,
Robert

> On 04 Feb 2021, at 17:53, Yanni M. <gianni.milo22 at gmail.com> wrote:
> 
> I don't know the internals of the Linstor database system but I'd guess that it updates itself each time you do a modification onto it like for example adding or removing resources, resource groups etc.
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> On Thu, 4 Feb 2021 at 05:47, Ferran Alchimia <ferran.alchimia at gmail.com> wrote:

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> The user guide talks about "regular backups" but it does not specify when does the controller database updates itself.

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