Re: VM Instance to Google Cloud SQL Migration

On Thu, 15 Nov 2018 at 07:06, Ian Lawrence Barwick <barwick(at)gmail(dot)com> wrote:
>
> 2018年11月15日(木) 17:19 Andreas Kretschmer <andreas(at)a-kretschmer(dot)de>:
> >
> > Am 15.11.2018 um 08:54 schrieb Sathish Kumar:
> > > We would like to migrate our Postgresql VM instance on Google Cloud
> > > Platform to Google Cloud SQL with a minimal downtime. As I checked, we
> > > have to export and import the SQL file and our database size is large
> > > and cannot afford longer downtime.
> > >
> > > Do any have solution to achieve this?.
> >
> > setup a replication from one to the other?
>
> Doesn't seem possible at the moment; here:
> https://cloud.google.com/sql/docs/postgres/replication/
> it says: "Cloud SQL for PostgreSQL does not yet support replication
> from an external
> master or external replicas for Cloud SQL instances."
>
> Looking at the feature list:
>
> https://cloud.google.com/sql/docs/postgres/features
>
> among the "Unsupported features" are: "Any features that require
> SUPERUSER privileges"
> (apart from a limited number of extensions), which pretty much rules
> out pglogical or similar solutions.

That usually also rules out Slony-I, although there's a possibility...

Slony-I includes a feature called log shipping, which could perhaps be used
for this, assuming that the "source" environment does allow superuser
privileges. (And I think you're running on a PostgreSQL instance where
that's possible...)

See: http://slony.info/documentation/logshipping.html

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