List:General Discussion« Previous MessageNext Message »
From:Walter Heck - OlinData.com Date:October 19 2010 11:37pm
Subject:Re: Master Master Replication ... do a fail over and a week agos data
is revealed.
View as plain text  
To Clarify this a bit: You can only reliably do writes to one server.
Your reads can go to both servers with no problems.
For reads that need to read data that was just written though, you
need to read from the 'active' master, as you can not rely on
replication to be instantaneous.

On Tue, Oct 19, 2010 at 20:07, Johan De Meersman <vegivamp@stripped> wrote:
> On Tue, Oct 19, 2010 at 1:03 PM, Carl <carl@stripped> wrote:
>
>> Johan,
>>
>> You state that master - master is not reliable in dual active environments.
>> I am in the process of setting up just such an environment (moderate active
>> on the primary server, lighter activity on the other server.)  Do you know
>> where I can get some information on the risks?
>>
>
> On the MySQL site, I guess :-) Your major issue is likely to be the lack of
> two-phase commits (which has been added in the most recent release, iirc):
> even if you properly interleave your autoincrements, the lack of a true
> global lock means you still risk conflicting updates.
>
> I can't really tell you a single spot where I got my knowledge on the
> subject - I'm a long-time and multi-platform DBA, so it's a combination of
> stuff I read and an understanding of how things work - or don't.
>
> --
> Bier met grenadyn
> Is als mosterd by den wyn
> Sy die't drinkt, is eene kwezel
> Hy die't drinkt, is ras een ezel
>



-- 
Walter Heck
Founder @ OlinData (http://olindata.com)
Co-founder @ Tribily (http://tribily.com)
Thread
Master Master Replication ... do a fail over and a week agos datais revealed.Brent Clark18 Oct
  • Re: Master Master Replication ... do a fail over and a week agos datais revealed.short cutter19 Oct
    • Re: Master Master Replication ... do a fail over and a week agos datais revealed.Johan De Meersman19 Oct
  • Re: Master Master Replication ... do a fail over and a week agos data is revealed.Carl19 Oct
    • Re: Master Master Replication ... do a fail over and a week agos datais revealed.Johan De Meersman19 Oct
      • Re: Master Master Replication ... do a fail over and a week agos datais revealed.Walter Heck - OlinData.com20 Oct
        • Re: Master Master Replication ... do a fail over and a week agos datais revealed.Johan De Meersman21 Oct