From: Joe Gainey
Date: July 28 2003 6:21pm
Subject: Re: Master/Master Asynchronous replication
List-Archive: http://lists.mysql.com/mysql/146311
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Well, the bad news is that I did not get any positive responses (that I 
can recall) from the list.  But I did a little digging.  suppossedly in 
the latest release you can do A->B->C->D->A.  Something to do with the 
server name encoded in the blog.  I'm not much of a dba but in todays ID 
sweatshops they are trying to squeeze me for all I got.  My official 
answer to the higher ups was "I know this can be done in Oracle" but at 
thier licensing costs there's no way.  If I get anything concrete going 
I'll drop a note to the list.


/Joe

Gaspar Bakos wrote:
> Hi, Joe,
> 
> I have exactly the same scenario. Did you get any valuable response you
> could share with me? I haven't seen any on the list.
> 
> In fact, my case is slightly more complicated; I have "N" computers, all
> having their local databases, and have an additional computer, which I
> call the "central" one, having a "central" copy of the database. I'd like
> to sync all the N+1 databases continuously, so they are identical.
> 
> 
>              A---C---B
>                  |
>                  D
> 
> That is, if I change anything on any PC's DB (e.g. "A"), it replicates
> itself to the central DB ("C"), and then migrates to "B" and "D". This
> means that the A<->C connection is such that "A" is a master and "C" is
> a slave, and the C<->B is such that C is a master and B is a slave. On
> the other hand, if I change something on another local DB than "A",
> e.g. "B" or "C" itself, I'd like this to migrate to "A", i.e. this case
> the A<->C connection is such that "A" is the slave.
> 
> Altogether, I'd need a continuous master-master replication between all
> DBs and "C". Similar to a RAID-1 array, just in the world of databases,
> and over TCP. Maybe there is a problem with my concept, and this solution
> of pushing for reliability will eventually cause chaos.
> 
> The Mysql manual does not mention master-master replication:
> "Starting in Version 3.23.15, MySQL supports one-way replication
> internally. One server acts as the master, while the other acts as the
> slave."
> 
> Cheers,
> Gaspar
>