Hi Ron,
> On Oct 29, 2023, at 16:38, Peter J. Holzer <hjp-pgsql@hjp.at> wrote:
> And this is where it would break down. The modifications can't be
> applied to the replica any more because the replica now contains
> checksums and the modifications don't. In the best case the replica
> would catch the discrepancy and refuse to apply the modifications which
> would lead to the loss of these modifications. In the worst case it
> would apply them anyway causing severe data corruption.
...
> Not just the file headers. Every single data block.
>
> (Ok, it looks like the space for the checksum is reserved even if
> checksums aren't enabled[1]. So at least pg_checksums doesn't have to
> move data around to enable them. But overwriting a page with a checksum
> with one without one would still be bad.)
Those are the kind of answers and insights I was looking for. Thank you very much.
Ok, I will do a reinit then.
Cheers
Paul