Re: pg_basebackup, manifests and backends older than ~12

At Mon, 13 Apr 2020 13:51:07 +0900, Michael Paquier <michael(at)paquier(dot)xyz> wrote in
> On Mon, Apr 13, 2020 at 11:52:51AM +0900, Kyotaro Horiguchi wrote:
> > Since I'm not sure about the work flow that contains taking a
> > basebackup from a server of a different version, I'm not sure which is
> > better between silently disabling and erroring out. However, it seems
> > to me, the option for replication slot is a choice of the way the tool
> > works which doesn't affect the result itself, but that for backup
> > manifest is about what the resulting backup contains. Therefore I
> > think it is better that pg_basebackup in PG13 should error out if the
> > source server doesn't support backup manifest but --no-manifest is not
> > specfied, and show how to accomplish their wants (, though I don't see
> > the wants clearly).
>
> Not sure what Robert and other authors of the feature think about
> that. What I am rather afraid of is somebody deciding to patch a
> script aimed at working across multiple backend versions to add
> unconditionally --no-manifest all the time, even for v13. That would
> kill the purpose of encouraging the use of manifests.

I don't object that since I'm not sure about the use case of
cross-version pg_basebackup.

> > By the way, if I specified --manifest-checksums, it complains about
> > incompatible options with a message that would look strange to the
> > user.
> >
> > pg_basebackup: error: --no-manifest and --manifest-checksums are incompatible options
> >
> > ("I didn't specified such an option..")
>
> How did you trigger that? I am able to only see this failure when
> using --manifest-checksums and --no-manifest together.

Mmm. Sorry for the noise. I might ran unpatched version for the time.

regards.

--
Kyotaro Horiguchi
NTT Open Source Software Center