Re: backup manifests

On 3/30/20 5:08 PM, Andres Freund wrote:
> 
> The data in the backup label isn't sufficient though. Without having
> parsed the timeline file there's no way to verify that the correct WAL
> is present. I guess we can also add client side tools to parse
> timelines, add command the fetch all of the required files, and then
> interpret that somehow.
> 
> But that seems much more complicated.
> 
> Imo it makes sense to want to be able verify that WAL looks correct even
> transporting WAL using another method (say archiving) and thus using
> pg_basebackup's -Xnone.
> 
> For the manifest to actually list what's required for the base backup
> doesn't seem redundant to me. Imo it makes the manifest file make a good
> bit more sense, since afterwards it actually describes the whole base
> backup.

FWIW, pgBackRest stores the backup WAL stop/start in the manifest. To 
get this information after the backup is complete requires parsing the 
.backup file which doesn't get stored in the backup directory by 
pg_basebackup. As far as I know, this is only accessibly to solutions 
that implement archive_command. So, pgBackRest could do that but it 
seems far more trouble than it is worth.

Regards,
-- 
-David
david@pgmasters.net