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 pyr@smallrivers.com)
Date: Wed, 21 Dec 2011 12:34:48 +0100
From: pyr@smallrivers.com
To: user@cassandra.apache.org
Subject: Handling topology changes
Message-ID: <20111221113448.GA26219@omega>
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User-Agent: Mutt/1.5.21 (2010-09-15)

Hi,

I wonder about the best strategy when a cluster sees changes in its
topology relatively often.

My main concern is how to handle the initial token for new nodes. If a
cluster is first created with 7 nodes for which the initial token is
calculated with the formula here:
http://wiki.apache.org/cassandra/Operations#Token_selection.

It seems as though two strategies can be applied:

* having a fixed amount of nodes with initial tokens and letting new
  ones auto bootstrap themselves
* recomputing tokens for the new number of nodes and using nodetool move
  for each of those

Is any of these right and are there other strategies ?

   - pyr