Re: Client connected to two servers in Glade

[Pascal Obry <p.obry@wanadoo.fr>]

Tomas Hlavaty <hlavaty@labe.felk.cvut.cz> writes:

> Maybe, the problem lies in that I have two RCI partitions which are the
> same, i.e. they provide the same services. So I can't write
> 
> ...
> Partition_A, Partition_B : Partition
> 
> for Partition_A'Host use "this.that.there"
> for Partition_B'Host use "some.where.else"
> 
> procedure Server_A is in Partition_A;
> procedure Server_B is in Partition_B;
> ...
> 
> as Frank suggests.
> 
> The situation is as follows:
> 
> +-------------+   +-------------+   +-------------+      
> +-------------+
> | Machine_A1  |   | Machine_A2  |   | Machine_A3  |  ...  | Machine_An 
> |
> | Partition_1 |   | Partition_1 |   | Partition_1 |       | Partition_1
> |
> +---------+---+   +---+-----+---+   +-------------+      
> +---+---------+
>           |           |     |                                 |
>           \-----+-----/     \-----+---------------------------/
>                 |                 |
>          +------+------+   +------+------+
>          | Machine_B1  |   | Machine_B2  |  ...
>          | Partition_2 |   | Partition_2 |
>          +-------------+   +-------------+
> 
> where Partition_1 is a program collecting data from somewhere (not
> interesting) that is executed on Machine_Ai as a daemon. Partition_2 is
> a program simultaneously displaying data collected by any two
> Partitions_1. A user specify Machine_Aj and Machine_Ak dynamically when
> he wants to execute a Partition_2 on Machine_Bl.
> 
> Isn't it to complicated? May be there is something wrong in the
> structure of the distributed system. Should it be partitioned in a
> different way?

Yes. What you described is not achievable with RCI. It is just not possible to
have 2 instances of the same RCI on the distributed application. You should
definitely have a look at the RACW. This will make this architecture possible.

In short:

- create a partation "Manager" that will server as a name server.

- create Partition_1 as a RACW partition, each one will register to the
  manager with a specific name (string)

- Partition_2 will request 2 Partition_1 using the name server.

This is a short description I agree. Have a look at the GLADE bank example
which is somehow similar. And be sure to read the documentation, as you seem
quite confused it could be possible that you have just skipped this step :)

Pascal.

-- 

--|------------------------------------------------------
--| Pascal Obry                           Team-Ada Member
--| 45, rue Gabriel Peri - 78114 Magny Les Hameaux FRANCE
--|------------------------------------------------------
--|         http://perso.wanadoo.fr/pascal.obry
--|
--| "The best way to travel is by means of imagination"