I think of multi-master more in the case of load-balancing, where multiple machines are all fulfilling the role of master at the same time on the same cluster. I can't picture how it would apply to multiple clusters. I'm not sure, maybe i'm not getting it, but multi-master seems like a subtlely different thing.
On Thu, Nov 27, 2014 at 1:23 AM, Nick Dimiduk <[email protected]> wrote: > I guess "multi-master" is the more common term for this kind of > replication. > > On Tue, Nov 25, 2014 at 11:05 AM, Demai Ni <[email protected]> wrote: > > > Agree with you guys. I also experienced difficulty to explain about > > Master-Master and cyclical to my users before, until I began to talk > about > > M-S only as building-block, which can be applied as one please. > > > > Just like to chime in another point, maybe the document should emphasize > > that the Master or Slave term is from *the perspective of > > 'table:columnFamly'*. It is often confused when using term as > > 'Master-cluster' or 'Slave-Cluster' as if the cluster as a whole is a > > Master/Slave. Unless the clusters are setup strictly as one-way > > replication. the Cluster often serves for both roles. > > > > Demai > > > > On Tue, Nov 25, 2014 at 9:21 AM, Andrew Purtell < > [email protected]> > > wrote: > > > > > > > > > On Nov 25, 2014, at 11:09 AM, Jean-Daniel Cryans < > [email protected]> > > > wrote: > > > > > > > > "A master can be > > > > slave too, and a slave a master, and cycles are allowed" since with > > just > > > > that you can build everything else. > > > > > > +1 > > > > > > > > > > > > > On Nov 25, 2014, at 11:09 AM, Jean-Daniel Cryans < > [email protected]> > > > wrote: > > > > > > > >> On Mon, Nov 24, 2014 at 8:29 PM, lars hofhansl <[email protected]> > > > wrote: > > > >> > > > >> Hmm... From that angle all we really have is master-slave > replication, > > > >> without limit as how it can be setup.A master can be slave too, and > a > > > slave > > > >> a master, and cycles are allowed. > > > >> I find "cyclical replication" more confusing than "master-master" > > > >> (although it's true that master-master is strictly a subset of > > cyclical > > > - > > > >> just a cycle of two). > > > > > > > > I agree with that. > > > > > > > > > > > >> We might want to scrap all the terms and just state (hopefully a bit > > > >> nicer) what I tried to say in the first two sentences above. > > > > > > > > One thing about "master-master" is that some audiences will get it > > right > > > > away, for example folks coming from the MySQL world, but maybe we > want > > to > > > > skip using it in our doc and just say what you wrote above "A master > > can > > > be > > > > slave too, and a slave a master, and cycles are allowed" since with > > just > > > > that you can build everything else. > > > > > > > > > > > >> -- Lars > > > >> > > > >> From: Misty Stanley-Jones <[email protected]> > > > >> To: [email protected] > > > >> Sent: Monday, November 24, 2014 7:26 PM > > > >> Subject: Replication terminology "master-master" > > > >> > > > >> Hi all, > > > >> > > > >> I think "master-master" is a term that should be re-thought. It is > not > > > >> really a "type" of replication, but refers to a characteristic of a > > > >> cluster, specifically a cluster which participates in multiple > > clusters > > > >> with different roles -- it is a slave in one cluster and a master in > > > >> another cluster. I think with the current terminology, people > confuse > > it > > > >> with "cyclical" replication, in which two clusters replicate to each > > > other, > > > >> and eventually each has all the data from both. > > > >> > > > >> Since master-master in this sense is really not a type of > > replication, I > > > >> think we should just scrap it. You can have master-slave replication > > or > > > >> cyclical replication, or a combination. With master-slave > > replication, a > > > >> cluster can fulfill both roles at the same time, as long as it is in > > > >> different clusters. This is easy to understand as a sort of > recursive > > > >> cascade. > > > >> > > > >> Am I explaining it right, and what do you guys think about changing > > our > > > >> terminology? > > > >> > > > >> Thanks, > > > >> Misty > > > >> > > > >> > > > >> > > > >> > > > > > >
