Re: Streaming Replication between PostGreSQL 9.2.2 on Red Hat and PostGreSQL 9.2.24 on Debian

On 05/21/2018 07:18 PM, Jonatan Evald Buus wrote:
> Hi there,
>
> I'm trying to configure streaming replication between a Red Hat server
> running PostGreSQL 9.2.2 and a Debian server running PostGreSQL 9.2.24
> with Hot Standby enabled.
>
> While the base backup works fine using /pg_basebackup/, I get the following
> errors with hot standby enabled on the Debian slave when starting PostGreSQL:

> /WARNING: WAL was generated with wal_level=minimal, data may be missing/
> /HINT: This happens if you temporarily set wal_level=minimal without taking a new base backup./
> /FATAL: hot standby is not possible because wal_level was not set to "hot_standby" on the master server/
> /HINT: Either set wal_level to "hot_standby" on the master, or turn off hot_standby here/
>
> If I turn Hot Standby off on the Debian Slave I get the following errors:
> /FATAL: database system identifier differs between the primary and standby/
> /DETAIL: The primary's identifier is 5940475598986796885, the standby's identifier is 6557962695089036503./

The standby clearly hasn't been cloned from the primary, otherwise the
identifiers would be the same. Are you sure the PostgreSQL instance
running on the standby is the one you backed up with pg_basebackup?

Regards

Ian Barwick

--
Ian Barwick http://www.2ndQuadrant.com/
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