> I assume here that you just have two databases, on two hosts, MST and
> CLI.

Yes. At least for the sake of this discussion.

> It is necessary that the slon process managing node MST is able to
> access both the MST and CLI hosts:
>
>   - It is managing node MST, so obviously must access it;
>   - It needs to be able to receive events and confirmations of events
>     from node CLI.

And here are my doubts. Do MST really needs to receive anything from CLI?
And what (which events and confirmations)?

Especially http://linuxfinances.info/info/plainpaths.html claims that
"You forcibly need to have a path between each subscriber node and its
provider; other paths are optional, and will not be used unless a
listen path in sl_listen. is needed that uses that particular path."

But, at the same time a few other docs claim what you do.

> If CLI is able to reach MST, then you could presumably run the slon
> processes managing both nodes on CLI.

I remember some strong advice against running slon across weak
connection. From http://linuxfinances.info/info/bestpractices.html:
"Each slon(1) should run on a host on the same local network as the
node that it is servicing, as it does a lot of communications with its
database" (...)  "slon(1) processes should run in the same "network
context" as the node that each is responsible for managing so that the
connection to that node is a "local" one. Do not run such links across
a WAN. "

-- 
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| Marcin Kasperski   |  In any large change, 1/3 will think it is
| http://mekk.waw.pl | great, 1/3 will think it is stupid, and 1/3
|                    |               will wait (Reed)
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