Re: Experience with replication wanted

I have done replication several times: snapshot, updatable snapshot, and n-way to as many as five nodes. Oracle says that n-way to two nodes, with snapshots off of each is "state of the art", and that "three nodes is pushing the envelope"... and that you will need "one full-time dba to handle collisions" (writing rules). My government customer where we replicated five nodes was doing this for the initial release, with an ultimate target of 19 nodes in the final product. I suspect that they were expecting technology to "catch up" by the time they got to the final product -- and it probably will... the project was cancelled after about three years. One thing about what they were doing though, even though everything was replicated everywhere, the data was regionally segmented so there would not be updates to data which did not belong in one of the other regions... Data distribution is an important consideration. It was to easy to say "replicate everything everywhere" and expect technology to take care of it -- instead of doing the required analysis....

As for the 64kb line... well, you must consider the volumn... not the size. Once it's replicated, if the volumn is low it can be done... if the volumn is high you must do the analysis and calculate the bandwidth.

If the updates are normally done at one location, or the data is segmented as I described above, collisions should not be a big problem. The rules are pretty straight forward.

David Russell

On Thu, 27 May 1999 17:22:20 +0200, <p.c.de.wolff_at_pve.agro.nl> wrote:

>Hi,
>
>Who has experience with replicating two oracle databases on a daily bases?
>
>I want to know what weere the problems, what type of replication do you use
>and how much work is it keeping it all in the air.
>We will be replicating a 500 mb database once a day over an 64kb line. Can
>it be done??
>
>Please respond directly to me.
>
>Peter de Wolff
>Productschappen Vee, Vlees en Eieren
>Rijswijk, the Netherlands.
>p.c.de.wolff_at_pve.agro.nl
>
>
Received on Thu May 27 1999 - 14:12:18 CDT