Re: PG Upgrade with hardlinks, when to start/stop master and replicas

On Fri, Feb 22, 2019 at 2:03 AM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> Bruce Momjian <bruce(at)momjian(dot)us> writes:
> > On Thu, Feb 21, 2019 at 09:31:32PM -0500, Stephen Frost wrote:
> >> * Bruce Momjian (bruce(at)momjian(dot)us) wrote:
> >>> There was too much concern that users would accidentally start the old
> >>> server at some later point, and its files would be hard linked to the
> >>> new live server, leading to disaster.
>
>
I think this is a great solution. Knowing that neither a human nor a
supervisor can mess up the hardlinks is something I really appreciate.

> >> Sure, I understand that concern, just wish there was a better approach
> >> we could use for "DO NOT START THIS SERVER" rather than moving of the
> >> pg_control file.
>
> > As ugly as it is, I have never heard of a better solution.
>
> system("rm -rf $OLDPGDATA") ... nah, that is not a better idea.
>
> regards, tom lane
>