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Date: Mon, 05 Mar 2012 07:42:42 -0800
From: David Koblas <david@koblas.com>
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To: user@cassandra.apache.org
Subject: Adding a second datacenter
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Everything that I've read about data centers focuses on setting things 
up at the beginning of time.

I've the the following situation:

10 machines in a datacenter (DC1), with replication factor of 2.

I want to set up a second data center (DC2) with the following 
configuration:
   20 machines with a replication factor of 4

What I've found is that if I initially start adding things, the first 
machine to join the network attempts to replicate all of the data from 
DC1 and fills up it's disk drive.  I've played with setting the 
storage_options to have a replication factor of 0, then I can bring up 
all 20 machines in DC2 but then start getting a huge number of read 
errors from read on DC1.

Is there a simple cookbook on how to add a second DC?  I'm currently 
trying to set the replication factor to 1 and do a repair, but that 
doesn't feel like the right approach.

Thanks,