On Thu, Feb 22, 2018 at 5:36 PM, Jean Carlo <jean.jeancar...@gmail.com>
wrote:

> Hello
>
> I would like to clarify this,
>
> In order to initialize  a  cassandra multi dc cluster, without data. If I
> follow the documentation datastax
>
> https://docs.datastax.com/en/cassandra/2.1/cassandra/initialize/
> initializeMultipleDS.html
>
> It says
>
>    - auto_bootstrap: false (Add this setting *only* when initializing a
>    clean node with no data.)
>
> But I dont understand the way this works regarding to the auto_bootstraps.
>
> If all the machines make their own tokens in a ramdon way using
> murmur3partitioner and vnodes , it isn't probable that two nodes will have
> the tokens in common ?
>

The key is not to start all nodes at the same time.  The token allocation
is random by default, but every node checks with the rest of the cluster to
see if a token has not been already taken, then it generates another random
one if needed.

It is recommended(where?) to wait for ~2 minutes between starting nodes in
a new cluster/DC.

> It is not better to bootstrap first the seeds with auto_bootstrap: false
> and then the rest of the nodes with auto_bootstrap: true ?
>
The auto_bootstrap setting has no influence on token allocation (unless you
want to use the new token allocation algorithm on version 3.0).  It only
allows you to skip streaming from the rest of the nodes, but since there is
no data in a brand new cluster, there is no practical difference.

Regards,
--
Alex

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