From: Marcus Bointon
Date: October 27 2011 7:06am
Subject: Re: Master-Master -> duplicate entry
List-Archive: http://lists.mysql.com/replication/2239
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On 27 Oct 2011, at 02:09, Ricardo wrote:

> In order to have a small redudant system, this is the way to go.
>=20
> I've made a mistake and allowed colisions to happen
>=20
> The increment-increment and offset increment will problably solve this=20=


Writing to both masters is not improving your redundancy - it's reducing =
it! If your replication fails then you've got incomplete data on BOTH =
servers, not just one. You really don't want to do it. This is why MMM =
sets the passive master to read-only. The increment offset will fix your =
clash problem, but that doesn't mean you should write to both at once.

As has been said many times, master-master replication is not a scaling =
solution.

Marcus
--=20
Marcus Bointon
Synchromedia Limited: Creators of http://www.smartmessages.net/
UK info@hand CRM solutions
marcus@stripped | http://www.synchromedia.co.uk/