On Fri, Aug 12, 2011 at 9:52 AM, Frank McGeough
<Frank.Mcgeough at vocalocity.com> wrote:
> I’ve read the documentation on upgrading and it appears the recommended
> approach is to drop replication and start over. Is this correct? Does anyone
> have any experience with performing the upgrade from 1.2 level up to 2?

Yes, you've got that correct.

There were pretty massive changes between 1.2 and 2.0.

I had started efforts on a would-be methodology to upgrade the Slony
schema, but it was getting complex enough, including requiring some
steps outside Slony (e.g. - the log triggers and XXID visibility
functions changed in ways that would be really troublesome to cope
with) that we concluded it wasn't realistic to "upgrade" but rather to
drop replication and reinstall Slony.  To aid in that, we added the
"OMIT COPY" option, so that you can install without having to
TRUNCATE/COPY all the data on subscriber nodes that are already up to
date.

There's tooling there (see tools/slonikconfdump.sh) to dump out the
cluster's configuration so that it is made as easy as possible to
re-install.