Обсуждение: recovery.conf

On 5 September 2016 at 10:50, Poul Kristensen <bcc5226@gmail.com> wrote:
> It is not obvious to me what is the minimum configuration of the
> recovery.conf?
>
> The online manuals does not give the exact minumum.
>
> Can anyone help?

The docs are written to describe how to setup various use cases.

The minimal config varies depending on what you are trying to achieve.

--
Simon Riggs                http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services

Poul Kristensen wrote:
> It is not obvious to me what is the minimum configuration of the recovery.conf?
> 
> The online manuals does not give the exact minumum.
> 
> Can anyone help?

None of the settings in recovery.conf must be specified.

One that you will almost always have for recovery is "restore_command", but if all
the WAL you need is in pg_xlog, you don't have to specify that either.
And you don't need it for streaming replication.

Some settings are necessary for point-in-time-recovery, and some
for streaming replication, which are two different use cases for the same recovery mechanism.
Maybe that's what's confusing you.

Yours,
Laurenz Albe

Poul Kristensen wrote:
> Sorry for asking a lot.
> 
>  pg_replication_slots.
> 
> is this meant to be a slot like a ethernetcard and controller in a physical server.

No, it is a data structure with which the PostgreSQL replication master can keep track how
far behind a replication slave is.
That way it can avoid discarding WAL that is needed by to replication slave to catch up.

Yours,
Laurenz Albe

On Tue, Sep  6, 2016 at 10:41:39AM +0200, Poul Kristensen wrote:
> Thanks a lot for fast responce.
>
> Do you have any idea of why PostgreSQL don't use cluster like normally used
>  e.g 
> One common disk for both master and nodes?

You can read our opinion of that solution here:


https://www.postgresql.org/message-id/flat/ncotsa$lhg$1@pye-srv-01.telemetry.co.uk#ncotsa$lhg$1@pye-srv-01.telemetry.co.uk

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  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

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