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

Thanks Ian, thank you for pointing out the obvious.
It appears that Debian's *pg_dropcluster* command had unexpected
consequences.... you live, you pull out your hair in frustration and you
learn.

I now have streaming replication working as we expected, can you confirm
that my *(somewhat unusual scenario?) *shouldn't cause any problems?
Specifically:
- Using Streaming Replication between two PostGreSQL instances with
different minor versions will work *(9.2.2 on RHEL and 9.2.24 on Debian)*
- Using Streaming Replication between two servers running different
operating systems *(RHEL 5.5 and Debian 8 / 9) *will work

Greatly appreciate your insight

Cheers
Jona

On 21 May 2018 at 13:27, Ian Barwick <ian(dot)barwick(at)2ndquadrant(dot)com> wrote:

> 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/
> PostgreSQL Development, 24x7 Support, Training & Services
>

--
Jonatan Evald Buus
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