Re: [HACKERS] Enabling replication connections by default inpg_hba.conf

On 2/3/17 17:47, Michael Paquier wrote:
> On Fri, Feb 3, 2017 at 4:59 AM, Simon Riggs <simon@2ndquadrant.com> wrote:
>>> It's weirdly inconsistent now.  You need a "replication" line in
>>> pg_hba.conf to connect for logical decoding, but you can't restrict that
>>> to a specific database because the database column in pg_hba.conf is
>>> occupied by the "replication" key word.
>> Agreed. Change needed.
> That sounds really apealling indeed after thinking about its
> implications. So we would simply authorize a WAL sender sending
> "replication" to connect if the user name matches. That's in short
> check_db() in hba.c.

In
<https://www.postgresql.org/message-id/7a33990f-75b1-5a4f-e7c0-223e15b84c11@2ndquadrant.com>
patch 0006 it is proposed to no longer use the "replication" keyword in
pg_hba.conf for logical
replication and use the normal database entries instead.

However, I don't think we can reasonably get rid of the replication
keyword for physical replication.  Say if you have a pg_hba.conf like

host  db1  someusers  ...
host  db2  someusers  ...
host  db3  someusers  ...

how would you decide access for physical replication?  Since physical
replication is not to a database, you need a way to call it out
separately if your pg_hba.conf style is to enumerate databases.

What we could do to make things simpler is to include "replication" in
the "all" keyword.

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
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