On Thu, 2010-02-04 at 22:39 -0800, Tory M Blue wrote:
> On Thu, Feb 4, 2010 at 6:02 PM, Andrew Sullivan <ajs at crankycanuck.ca> wrote:
> > On Thu, Feb 04, 2010 at 03:39:03PM -0800, Tory M Blue wrote:
> >> Slon 1.2.20 (For now as I migrate to 8.4 )
> >>
> >> Just working out a new Slon setup, with a cascade configuration.
> >>
> >> ! master talking to 2 Slaves (if not more), that talk to 2-3 Qslaves.
> >>
> >> Is it wrong to have both Slaves talking, replicating to both QSlaves?
> >
> > When you say "replicating to", do you mean they're both actively
> > sending data to the other replicas?  If so, then it won't work.  Only
> > one can be the set origin for a given target at a time.  But they can
> > both be forwarders, such that one could take over for the other.
> >
> > A
> >
> 
> Thanks Andrew
> 
> Ahh interesting, yes I have it setup so that 2 and 3 both send
> (forward) data to 4 and 5.. the paths take, listeners are created but
> I had a feeling this may not be wise. Are you sure it doesn't work? I
> think I have it working, but if it's frowned upon or otherwise
> questionable, I'll change my path.

Having the paths in place is fine. The extra paths will increase the
communications cost, but can be safer and simply your DR.

I think you have the concept wrong.  For a given set, data flows from a
single provider to a single subscriber.  This is a unique one-to-one
pairing.  You can have as many of these pairing as you can support, and
they can be cascaded (a node is both a subscriber and a provider for the
same set).  

All the paths are are channels for communication (which will also move
data if appropriate).

> Also to include more info. I have 3 sets.
> 
> sets 1,2,3 are on the master and the 2 slaves (master replicating
> (actively sending data to  both slaves).  I could fail-over between
> these 3 nodes.
> 
> set 1 is only replicated between the slaves (2 and 3) and the Qslaves
> ( 4 and 5).
> 2-4
> 3-4
> 2-5
> 3-5
> 
> Master and Slaves are forwarders. Qslaves are non forwarders
> 
> Still wrong, even if I "Think" I have it working?

I don't see anything wrong with this config.

-- 
Brad Nicholson  416-673-4106
Database Administrator, Afilias Canada Corp.