Re: [GENERAL] How does BDR replicate changes among nodes in a BDRgroup

Thanks for the clarification.

A follow up question, then, given *once joined all nodes are equal*, is that:

should the node A dies or taken out of the group, the remaining three node group (with B, C and D) would continue to
functionproperly, correct?
 
[somewhere I saw the term "downstream" nodes was used, and I am not clear what that meant in the context of a
mesh-connectedgroup] 
 

Thanks again

-----Original Message-----
From: Craig Ringer [mailto:craig@2ndquadrant.com] 
Sent: Wednesday, June 07, 2017 5:59 PM
To: Zhu, Joshua <jzhu@thalesesec.net>
Cc: pgsql-general@postgresql.org
Subject: Re: [GENERAL] How does BDR replicate changes among nodes in a BDR group

On 8 June 2017 at 04:50, Zhu, Joshua <jzhu@vormetric.com> wrote:

> How does BDR replicate a change delta on A to B, C, and D?

It's a mesh.

Once joined, it doesn't matter what the join node was, all nodes are equal.

> e.g., A
> replicates delta to B and D, and B to C, or some other way, or not 
> statically determined?

Each node replicates to all other nodes in an undefined order determined by network timing etc.


-- 
 Craig Ringer                   http://www.2ndQuadrant.com/
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