Re: MultiMaster Replication Using Dialup - Newbie Question

It will work but...

Multimaster replication doesn't come to a screeching halt if a site goes down. But rows build up in the active master sites until they are applied to the downed site and this is not good. This situation increases the possibility (or likelihood) of conflicts due to timing issues or network issues. Let's say New York and Tokyo are up and Nagoya goes down. During this period New York adds a row and Tokyo immediately modfies it. When Nagoya comes up, Tokyo's modification may reach Nagoya faster than New York's addition. Now you have a conflict to resolve - or you have to have designed a really bombproof set of conflict avoidance rules. The more sites in your setup the worse this kind of problem can be to untangle.

In general you should design for the fact that there will be unplanned outages from time to time but you probably should be very careful using multimaster replication if you plan to have regular outages at one or more sites.

On the other hand, if you are using dialup connections, perhaps your system is very small and the likelihood of conflicts also very small.

"JDM" <jdmampilly_at_hotmail.com> wrote in message news:1f66e638.0406140242.2466b795_at_posting.google.com...
> Hi all,
> We are trying to setup a Multimaster Replication environment between
> multiple sites using Oracle 9.2.0.1.0 databases.
> The sites will be connected using dialup.
> Replication between two sites which was setup works fine, now we need
> to set up a third site. The question is will replication work if one
> of the sites is not connected (ie can we connect two sites at a time
> and do the replication process.)
>
> Any helpful hints will be appreciated
>
> Joseph.
Received on Mon Jun 14 2004 - 11:40:22 CDT