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From Mark Moseley <moseleym...@gmail.com>
Subject Re: Newbie Replication/Cluster Question
Date Thu, 13 Jan 2011 22:32:01 GMT
On Thu, Jan 13, 2011 at 1:08 PM, Gary Dusbabek <gdusbabek@gmail.com> wrote:
> It is impossible to properly bootstrap a new node into a system where
> there are not enough nodes to satisfy the replication factor.  The
> cluster as it stands doesn't contain all the data you are asking it to
> replicate on the new node.

Ok, maybe I'm thinking of replication_factor backwards. I took it to
mean how many nodes would have *full* copies of the whole of the
keyspace's data, in which case with my keyspace with
replication_factor=2 the still-alive node would have 100% of the data
to replicate to the wiped-clean node--in which case all the data would
be there to bootstrap. I was assuming replication_factor=2 in a 2-node
cluster == both nodes having a full replica of the data. Do I have
that wrong?

What's also confusing is that I did this same test on a clean node
that wasn't clustered yet (which is interesting that it doesn't
complain then about replication_factor > # of nodes), so unless it was
throwing away data as I was inserting it, it'd all be there.

Is the general rule then that the max. replication factor must be
#_of_nodes-1 then? If replication_factor==#_of_nodes, then if you lost
a box, it seems like your cluster would be toast.

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