Which parameters are only used on startup?
The following documentation comment has been logged on the website:
Page: https://www.postgresql.org/docs/18/runtime-config-connection.html
Description:
Clarify that ssl_cert_file and ssl_key_file are only read on startup --
implying that the params can be changed and the files moved to the new
location/name without requiring a restart. Of course a restart is good to
validate that the params and files are configured correctly.
On Wed, Nov 26, 2025 at 09:34:18AM +0000, PG Doc comments form wrote:
The following documentation comment has been logged on the website:
Page: https://www.postgresql.org/docs/18/runtime-config-connection.html
Description:Clarify that ssl_cert_file and ssl_key_file are only read on startup --
implying that the params can be changed and the files moved to the new
location/name without requiring a restart. Of course a restart is good to
validate that the params and files are configured correctly.
The docs say that you can only change this in postgresql.conf or on the
command line. Changes to postgresql.conf requires pg_ctl reload or
something similar.
I am not aware of anyone else who thinks changing postgresql.conf and
then reloading causes the session to use new ssl keys/files, and
explaining that in the docs might be more confusing than helpful.
--
Bruce Momjian <bruce@momjian.us> https://momjian.us
EDB https://enterprisedb.com
Do not let urgent matters crowd out time for investment in the future.
Bruce Momjian <bruce@momjian.us> writes:
On Wed, Nov 26, 2025 at 09:34:18AM +0000, PG Doc comments form wrote:
Clarify that ssl_cert_file and ssl_key_file are only read on startup --
implying that the params can be changed and the files moved to the new
location/name without requiring a restart. Of course a restart is good to
validate that the params and files are configured correctly.
The docs say that you can only change this in postgresql.conf or on the
command line. Changes to postgresql.conf requires pg_ctl reload or
something similar.
The actual problem with this change request is that it's wrong.
We've supported changing ssl_cert_file --- either the GUC value
or the file contents --- via "pg_ctl reload" or equivalent for
years now (cf. commits de41869b6, 6667d9a6d). So I don't see
anything wrong with the docs text as it stands.
regards, tom lane
On Mon, Dec 22, 2025 at 07:29:10PM -0500, Tom Lane wrote:
Bruce Momjian <bruce@momjian.us> writes:
On Wed, Nov 26, 2025 at 09:34:18AM +0000, PG Doc comments form wrote:
Clarify that ssl_cert_file and ssl_key_file are only read on startup --
implying that the params can be changed and the files moved to the new
location/name without requiring a restart. Of course a restart is good to
validate that the params and files are configured correctly.The docs say that you can only change this in postgresql.conf or on the
command line. Changes to postgresql.conf requires pg_ctl reload or
something similar.The actual problem with this change request is that it's wrong.
We've supported changing ssl_cert_file --- either the GUC value
or the file contents --- via "pg_ctl reload" or equivalent for
years now (cf. commits de41869b6, 6667d9a6d). So I don't see
anything wrong with the docs text as it stands.
I had trouble parsing his text too but I think the original poster's
point was that changing these values don't affect a connected session.
When the original poster says restart, I think he/she means restart the
session, not the postmaster, but I am not 100% clear on that either.
--
Bruce Momjian <bruce@momjian.us> https://momjian.us
EDB https://enterprisedb.com
Do not let urgent matters crowd out time for investment in the future.