Alan Hodgson wrote:
> On Tuesday 27 June 2006 09:09, Dan Fitzpatrick <dan at eparklabs.com> wrote:
>   
>> Can Slony handle the following setup:
>>
>>
>> Internal |   DMZ   | External
>> Network  |         | Network
>> ---------|---------|---------
>>  Master  -> Bridge -> Slave
>>    DB         DB       DB
>>
>>
>> In this case, Bridge DB is a slony slave which is the "master" of the
>> external Slave DB.
>>
>> I have a large DB (master) and I want to replicate 2 - 3 tables to an
>> outside server. However, I do not want the master exposed to the outside
>> directly.
>>
>> If this setup does not work with Slony, do you know how else to do this?
>>     
>
> That would work.  
>
> However, you can also just run the slon process serving the external DB on 
> an internal server.  ie. the external server requires no access back to the 
> internal server.
>
>
>   
Thanks for your feedback.

Just to clarify: The slon process could run on the server not running 
the DB (The "bridge" server in my case). So the design would look like this:

Internal |   DMZ   | External
Network  |         | Network
---------|---------|---------
 Master  -> Slon   -> Slave
   DB       Proc       DB

A few more questions:

 1. On http://gborg.postgresql.org/project/slony1/genpage.php?howto_basic it says: "The REPLICATIONUSER needs to be PostgreSQL superuser.  This is typically postgres or pgsql." So the slave would not have to have superuser access to the master? 

 2. Slon would need superuser access to the master and the slave?

 3. Does the slave need to initiate network connections _to_ slon or just accept connections from slon? If the slave initiates connections to slon, what port does this happen on?

 4. Do two slon processes need to run (one for the master and one for the slave) and the two slons talk?

Thanks for your answers.

Dan