Re: Set new system identifier using pg_resetxlog

On Fri, Jun 13, 2014 at 8:31 PM, Petr Jelinek <petr@2ndquadrant.com> wrote:
> 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 can clearly understand the utility of being able to reset the system
ID to a new, randomly-generated system ID - but giving the user the
ability to set a particular value of their own choosing seems like a
pretty sharp tool.  What is the use case for that?

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company