From: Tom Lane <tgl@sss.pgh.pa.us>
To: Benjamin Wang <benjamin.ahrtr@gmail.com>
cc: "Peter J. Holzer" <hjp-pgsql@hjp.at>, pgsql-general@lists.postgresql.org
Subject: Re: Bypassing Directory Ownership Check in PostgreSQL 16.6 with Secure z/OS NFS (AT-TLS)
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Comments: In-reply-to Benjamin Wang <benjamin.ahrtr@gmail.com>
	message dated "Mon, 14 Jul 2025 20:02:27 +0100"
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Date: Mon, 14 Jul 2025 15:10:45 -0400
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Benjamin Wang <benjamin.ahrtr@gmail.com> writes:
> I am not sure whether PostgreSQL depends on system call `fsyncdata` to
>  sync data to disk. If yes, then I don't think it's safe to use NFS.

Well, that's a whole other discussion.  The point about mount
directories applies to any sort of dismountable storage.

(But I too would not use Postgres-over-NFS for any critical data.
Too many moving parts.  It's tough enough to ensure crash safety
with local storage.)

			regards, tom lane