Re: Cascading replication: should we detect/prevent cycles?

On 19 December 2012 08:11, Joshua D. Drake <jd(at)commandprompt(dot)com> wrote:
>
> On 12/18/2012 11:57 PM, Simon Riggs wrote:
>>
>>
>> On 19 December 2012 03:03, Josh Berkus <josh(at)agliodbs(dot)com> wrote:
>>
>>> So, my question is:
>>>
>>> 1. should we detect for replication cycles? *Can* we?
>>> 2. should we warn the user, or refuse to start up?
>>
>>
>> Why not just monitor the config you just created? Anybody that
>> actually tests their config would spot this.
>
>
> I think you are being optimistic. We should probably have some logic that
> prevents circular replication.

My logic is that if you make a 1 minute test you will notice your
mistake, which is glaringly obvious. That is sufficient to prevent
that mistake, IMHO.

If you don't test your config and don't monitor either, good luck with HA.

Patches welcome, if you think this important enough.

--
Simon Riggs http://www.2ndQuadrant.com/
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