On Wed, 27 Feb 2019, SAS wrote:

If you don't have paths between two nodes then there won't be a connection 
between them.

If your not going to have a complete network of paths then you should 
consider failure cases in determining how many paths you really need.




> 
> Hello,
> 
> We have a slony cluster with 11 nodes, and 3 sets. All PostgreSQL servers are still running a
> 9.2.x version. The upgrade of Slony is part of the PostgreSQL nodes upgrades, as we have to run a
> more recent version, so as to be able to insert PG 11 nodes in the cluster.
> 
> The replication topology is as follow:
> 
> Set 1 :
> 
> 1 --- 2
> \ --- 3 --- 4
>         \ --- 5
>         \ --- 6
>         \ --- 7
>         \ --- 8
>         \ --- 9
>         \ --- 10
>         \ --- 11
> 
> Set 2:
> 
> 11 --- 12
> \ --- 3 --- 4
>         \ --- 5
>         \ --- 6
>         \ --- 7
>         \ --- 8
>         \ --- 9
>         \ --- 1
>         \ --- 2
> 
> Set 3:
> 
> 1 --- 2
> \ --- 3 --- 11
>         \ --- 12
> 
> All slon daemons run on node 3.
> 
> When running slony 2.1.3, we had at most 20 or 25 connections on every database. Once we upgraded
> to slony 2.2.7, we ended up with 107 slony connections on every node.
> 
> Is it a normal behaviour? Is there a way to lower that number, as not every node needs to contact
> every other node?
> 
> Best, 
> 
> --
> Dr Stéphane Schildknecht
> Contact régional PostgreSQL pour l'Europe francophone
> +33 617 11 37 42
> 
> 
>