Re: Set new system identifier using pg_resetxlog

Josh Berkus wrote:
> On 06/13/2014 05:31 PM, Petr Jelinek wrote:
> > Hello,
> > 
> > attached is a simple patch which makes it possible to change the system
> > identifier of the cluster in pg_control. This is useful for
> > individualization of the instance that is started on top of data
> > directory produced by pg_basebackup - something that's helpful for
> > logical replication setup where you need to easily identify each node
> > (it's used by Bidirectional Replication for example).
> 
> I'm unclear on why we would overload pg_resetxlog for this.  Wouldn't it
> be better design to have an independant function,
> "pg_set_system_identifier"?

We have overloaded pg_resetxlog for all pg_control-tweaking needs.  I
don't see any reason to do differently here.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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