postgresql.conf RH comment, and a systemd RH note

Hi,

FYI, the RH rpm contains the following comment in postgresql.conf,
which is not in the postgresql.org rpm. I found it helpful.

@@ -61,11 +61,7 @@
# defaults to 'localhost'; use
'*' for all # (change requires restart)
#port = 5432 # (change requires restart)
-# Note: In RHEL/Fedora installations, you can't set the port number
here;
-# adjust it in the service file instead.
max_connections = 100 # (change requires restart)

There is also, by the by, a difference in the way the RHEL
postgresql package has systemd configured. In RHEL the
postgresql.service file contains a comment that says
to include it and then follow with changes in
/etc/systemd/system/postgresql.service.d/postgresql.service

(The path is what matters, I'm not sure about the
file name.)

But, the "standard RHEL way" to modify the default
systemd config for a service is instead to have files
ending in ".conf", and you don't have to include the original
service file. So this is the approach to take when installing
the upstream PG rpms. You make a file, e.g,
/etc/systemd/system/postgresql-9.5.service.d/postgresql-9.5.service.conf

(I'm not sure the file name matters, except for ending
in ".conf".)

According to the docs you should not have to start the
file by including the original service file (in
/usr/lib/systemd/system/), but it does not seem to hurt
to do so.

Anyhow, it makes sense to have the upstream PG rpms
use the "standard RH way" to configure systemd.
But if you're used to coming from the stock RH
rpm the change can lead to confusion.

Karl <kop(at)meme(dot)com>
Free Software: "You don't pay back, you pay forward."
-- Robert A. Heinlein