We are doing something very similar and it works fine.   Two 8.4 nodes and
one 8.3, with Slony 2.0.2.

The slony build has to be built against the version of Postgres on the
machine it will run on.  So the easiest way is to have a single Slony 2.0.3
build against 8.4, and run all your slon processes on one of the 8.4
servers.  That's how we run.  Or if you prefer to run distributed slons, you
can build a separate 2.0.3 Slony against 8.3 for the 8.3 server.  

You may get a warning about versions at startup, but it can be ignored so
long as you don't start using 8.4-specific data features (not sure what they
are).

Hope that helps
-gordon


Dan Sugalski wrote:
> 
> I've currently got a three node cluster in production running Slony 
> 2.0.2 and PG 8.3.7. It's ticking along pretty happily, and I'm 
> looking to toss a PG 8.4.1 node in to test the version upgrade.
> 
> What I'm wondering is whether it's okay to install Slony 2.0.3 RC2 on 
> the new 8.4.1 node
> 

-- 
View this message in context: http://www.nabble.com/Mixing-slony-versions-in-a-cluster--tp25464916p25465419.html
Sent from the Slony-I -- General mailing list archive at Nabble.com.